Computer — Computer and server systems
Computer: Programmable hardware that processes input and stores or emits results. This card shows its role in “Computer and server systems” and a safe diagnostic path.
Open learning card →Public mini-study
Self-hosting & operations
Learn how web services, containers, databases, media pipelines and local AI work together — from first orientation to independent operations and debugging.
0%1024 terms
Structure
32 × 32
Languages
Deutsch + English
Depth
Level 0–3
Focus
Operations & debugging
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Level 0 · Module 1Computer and server systemsFundamentals, operations, and troubleshooting for Computer and server systems.32 terms
Server — Computer and server systems
Server: A system that continuously provides services or data to other systems. This card shows its role in “Computer and server systems” and a safe diagnostic path.
Open learning card →Client — Computer and server systems
Client: A program or device that requests a service from a server. This card shows its role in “Computer and server systems” and a safe diagnostic path.
Open learning card →Host — Computer and server systems
Host: The operating system or machine on which a process or virtual environment runs. This card shows its role in “Computer and server systems” and a safe diagnostic path.
Open learning card →Hardware — Computer and server systems
Hardware: The physical components of a computer, such as CPU, RAM, and storage. This card shows its role in “Computer and server systems” and a safe diagnostic path.
Open learning card →Software — Computer and server systems
Software: Executable programs and data that determine hardware behaviour. This card shows its role in “Computer and server systems” and a safe diagnostic path.
Open learning card →Operating system — Computer and server systems
Operating system: The layer that manages hardware and provides processes, files, and networking to programs. This card shows its role in “Computer and server systems” and a safe diagnostic path.
Open learning card →Kernel — Computer and server systems
Kernel: The privileged core of an operating system that controls hardware access and resources. This card shows its role in “Computer and server systems” and a safe diagnostic path.
Open learning card →Linux distribution — Computer and server systems
Linux distribution: A Linux kernel bundled with package management, system tools, and maintained packages. This card shows its role in “Computer and server systems” and a safe diagnostic path.
Open learning card →Ubuntu Server — Computer and server systems
Ubuntu Server: An Ubuntu distribution aimed at server operation without requiring a desktop interface. This card shows its role in “Computer and server systems” and a safe diagnostic path.
Open learning card →CPU — Computer and server systems
CPU: The processor that executes machine instructions and coordinates computation. This card shows its role in “Computer and server systems” and a safe diagnostic path.
Open learning card →CPU core — Computer and server systems
CPU core: A largely independent execution unit inside a CPU. This card shows its role in “Computer and server systems” and a safe diagnostic path.
Open learning card →Thread — Computer and server systems
Thread: A schedulable flow of control within a process. This card shows its role in “Computer and server systems” and a safe diagnostic path.
Open learning card →RAM — Computer and server systems
RAM: Volatile working memory for currently needed code and data. This card shows its role in “Computer and server systems” and a safe diagnostic path.
Open learning card →Memory utilization — Computer and server systems
Memory utilization: The occupied portion of memory, including useful caches. This card shows its role in “Computer and server systems” and a safe diagnostic path.
Open learning card →Swap — Computer and server systems
Swap: Disk space into which the kernel can move infrequently used memory pages. This card shows its role in “Computer and server systems” and a safe diagnostic path.
Open learning card →Mass storage — Computer and server systems
Mass storage: Non-volatile storage for persistently retained data. This card shows its role in “Computer and server systems” and a safe diagnostic path.
Open learning card →HDD — Computer and server systems
HDD: A magnetic storage device with mechanically moving read/write heads. This card shows its role in “Computer and server systems” and a safe diagnostic path.
Open learning card →SSD — Computer and server systems
SSD: A non-volatile flash storage device without moving parts. This card shows its role in “Computer and server systems” and a safe diagnostic path.
Open learning card →File system — Computer and server systems
File system: The data structures and rules used to organise files on a storage device. This card shows its role in “Computer and server systems” and a safe diagnostic path.
Open learning card →Partition — Computer and server systems
Partition: A logically delimited region of a block device. This card shows its role in “Computer and server systems” and a safe diagnostic path.
Open learning card →Mount point — Computer and server systems
Mount point: The directory where a file system is attached to the directory tree. This card shows its role in “Computer and server systems” and a safe diagnostic path.
Open learning card →Network interface — Computer and server systems
Network interface: The logical or physical endpoint through which a host sends and receives network packets. This card shows its role in “Computer and server systems” and a safe diagnostic path.
Open learning card →GPU — Computer and server systems
GPU: A highly parallel processor for graphics and compute workloads. This card shows its role in “Computer and server systems” and a safe diagnostic path.
Open learning card →VRAM — Computer and server systems
VRAM: Fast memory used directly by a GPU for models, textures, and intermediate results. This card shows its role in “Computer and server systems” and a safe diagnostic path.
Open learning card →NVIDIA driver — Computer and server systems
NVIDIA driver: The kernel and user-space components connecting the operating system to an NVIDIA GPU. This card shows its role in “Computer and server systems” and a safe diagnostic path.
Open learning card →System time — Computer and server systems
System time: The current time maintained by the operating system for logs, certificates, and schedules. This card shows its role in “Computer and server systems” and a safe diagnostic path.
Open learning card →Time zone — Computer and server systems
Time zone: A rule set that converts UTC into local time including daylight-saving changes. This card shows its role in “Computer and server systems” and a safe diagnostic path.
Open learning card →Hostname — Computer and server systems
Hostname: The local name identifying a computer in the system and often on the network. This card shows its role in “Computer and server systems” and a safe diagnostic path.
Open learning card →Reboot — Computer and server systems
Reboot: A controlled restart of the operating system and its services. This card shows its role in “Computer and server systems” and a safe diagnostic path.
Open learning card →Shutdown — Computer and server systems
Shutdown: The controlled stopping of services and powering down of a system. This card shows its role in “Computer and server systems” and a safe diagnostic path.
Open learning card →Availability — Computer and server systems
Availability: The proportion of time during which a service is usable as intended. This card shows its role in “Computer and server systems” and a safe diagnostic path.
Open learning card →Level 0 · Module 2Files, paths, and directoriesFundamentals, operations, and troubleshooting for Files, paths, and directories.32 terms
File — Files, paths, and directories
File: A named sequence of bytes with metadata in a file system. This card shows its role in “Files, paths, and directories” and a safe diagnostic path.
Open learning card →Directory — Files, paths, and directories
Directory: A file-system object that maps names to files and subdirectories. This card shows its role in “Files, paths, and directories” and a safe diagnostic path.
Open learning card →Absolute path — Files, paths, and directories
Absolute path: A path that starts at the root and is unambiguous regardless of the working directory. This card shows its role in “Files, paths, and directories” and a safe diagnostic path.
Open learning card →Relative path — Files, paths, and directories
Relative path: A path resolved relative to the current or specified starting directory. This card shows its role in “Files, paths, and directories” and a safe diagnostic path.
Open learning card →Working directory — Files, paths, and directories
Working directory: The directory from which a process resolves relative paths. This card shows its role in “Files, paths, and directories” and a safe diagnostic path.
Open learning card →Root directory — Files, paths, and directories
Root directory: The topmost node of a file-system directory tree. This card shows its role in “Files, paths, and directories” and a safe diagnostic path.
Open learning card →Home directory — Files, paths, and directories
Home directory: The personal default directory of a user account. This card shows its role in “Files, paths, and directories” and a safe diagnostic path.
Open learning card →Hidden file — Files, paths, and directories
Hidden file: A file whose Unix name begins with a dot and is therefore often hidden. This card shows its role in “Files, paths, and directories” and a safe diagnostic path.
Open learning card →File extension — Files, paths, and directories
File extension: The suffix after the final dot in a name, commonly indicating format or purpose. This card shows its role in “Files, paths, and directories” and a safe diagnostic path.
Open learning card →File name — Files, paths, and directories
File name: The directory entry name used to address a file. This card shows its role in “Files, paths, and directories” and a safe diagnostic path.
Open learning card →Case sensitivity — Files, paths, and directories
Case sensitivity: The property of treating upper- and lower-case letters in names as distinct. This card shows its role in “Files, paths, and directories” and a safe diagnostic path.
Open learning card →Symbolic link — Files, paths, and directories
Symbolic link: A special file that stores another path as its target. This card shows its role in “Files, paths, and directories” and a safe diagnostic path.
Open learning card →Hard link — Files, paths, and directories
Hard link: An additional directory name for the same inode and file content. This card shows its role in “Files, paths, and directories” and a safe diagnostic path.
Open learning card →Inode — Files, paths, and directories
Inode: The file-system structure holding metadata and block references but not the file name. This card shows its role in “Files, paths, and directories” and a safe diagnostic path.
Open learning card →Owner — Files, paths, and directories
Owner: The user account assigned to a file-system object. This card shows its role in “Files, paths, and directories” and a safe diagnostic path.
Open learning card →Group — Files, paths, and directories
Group: A set of user accounts that can be granted shared permissions. This card shows its role in “Files, paths, and directories” and a safe diagnostic path.
Open learning card →File permissions — Files, paths, and directories
File permissions: Rules allowing read, write, and execute operations for owner, group, and others. This card shows its role in “Files, paths, and directories” and a safe diagnostic path.
Open learning card →Read permission — Files, paths, and directories
Read permission: Permission to read file content or list directory names. This card shows its role in “Files, paths, and directories” and a safe diagnostic path.
Open learning card →Write permission — Files, paths, and directories
Write permission: Permission to modify file content or create and remove directory entries. This card shows its role in “Files, paths, and directories” and a safe diagnostic path.
Open learning card →Execute permission — Files, paths, and directories
Execute permission: Permission to execute a file or traverse a directory. This card shows its role in “Files, paths, and directories” and a safe diagnostic path.
Open learning card →umask — Files, paths, and directories
umask: A bit mask that removes default permissions when files are created. This card shows its role in “Files, paths, and directories” and a safe diagnostic path.
Open learning card →Recursive operation — Files, paths, and directories
Recursive operation: An operation that traverses a directory and its complete subtree. This card shows its role in “Files, paths, and directories” and a safe diagnostic path.
Open learning card →Glob pattern — Files, paths, and directories
Glob pattern: A shell pattern such as `*.log` that expands to matching path names. This card shows its role in “Files, paths, and directories” and a safe diagnostic path.
Open learning card →File size — Files, paths, and directories
File size: The number of bytes logically stored in a file. This card shows its role in “Files, paths, and directories” and a safe diagnostic path.
Open learning card →Free disk space — Files, paths, and directories
Free disk space: Storage capacity not yet occupied and available for new data. This card shows its role in “Files, paths, and directories” and a safe diagnostic path.
Open learning card →Temporary file — Files, paths, and directories
Temporary file: A file for short-lived intermediate data that may be removed after use. This card shows its role in “Files, paths, and directories” and a safe diagnostic path.
Open learning card →Lock file — Files, paths, and directories
Lock file: A file used by processes to coordinate ownership or exclusive work. This card shows its role in “Files, paths, and directories” and a safe diagnostic path.
Open learning card →Configuration file — Files, paths, and directories
Configuration file: A file storing mutable program settings outside the code. This card shows its role in “Files, paths, and directories” and a safe diagnostic path.
Open learning card →Log file — Files, paths, and directories
Log file: An append-oriented file containing time-ordered operational and error messages. This card shows its role in “Files, paths, and directories” and a safe diagnostic path.
Open learning card →Binary file — Files, paths, and directories
Binary file: A file whose bytes are not directly interpreted as readable text. This card shows its role in “Files, paths, and directories” and a safe diagnostic path.
Open learning card →Text file — Files, paths, and directories
Text file: A file whose characters are read using a character encoding. This card shows its role in “Files, paths, and directories” and a safe diagnostic path.
Open learning card →Character encoding — Files, paths, and directories
Character encoding: The mapping between characters and their stored byte sequences. This card shows its role in “Files, paths, and directories” and a safe diagnostic path.
Open learning card →Level 0 · Module 3Shell fundamentalsFundamentals, operations, and troubleshooting for Shell fundamentals.32 terms
Shell — Shell fundamentals
Shell: A program that reads and expands commands and starts programs. This card shows its role in “Shell fundamentals” and a safe diagnostic path.
Open learning card →Bash — Shell fundamentals
Bash: A common Unix shell with a scripting language and interactive command line. This card shows its role in “Shell fundamentals” and a safe diagnostic path.
Open learning card →Terminal — Shell fundamentals
Terminal: An interface presenting input and output for a shell or console program. This card shows its role in “Shell fundamentals” and a safe diagnostic path.
Open learning card →Prompt — Shell fundamentals
Prompt: The shell input marker showing readiness and often contextual information. This card shows its role in “Shell fundamentals” and a safe diagnostic path.
Open learning card →Command — Shell fundamentals
Command: The name of a program or shell built-in to execute. This card shows its role in “Shell fundamentals” and a safe diagnostic path.
Open learning card →Argument — Shell fundamentals
Argument: A positional value passed to an invoked program. This card shows its role in “Shell fundamentals” and a safe diagnostic path.
Open learning card →Option — Shell fundamentals
Option: A usually named switch that changes command behaviour. This card shows its role in “Shell fundamentals” and a safe diagnostic path.
Open learning card →Exit code — Shell fundamentals
Exit code: An integer through which a process reports success or failure to its caller. This card shows its role in “Shell fundamentals” and a safe diagnostic path.
Open learning card →Standard output — Shell fundamentals
Standard output: The normal output stream of a process, file descriptor 1. This card shows its role in “Shell fundamentals” and a safe diagnostic path.
Open learning card →Standard error — Shell fundamentals
Standard error: The separate diagnostic output stream of a process, file descriptor 2. This card shows its role in “Shell fundamentals” and a safe diagnostic path.
Open learning card →Standard input — Shell fundamentals
Standard input: The input stream of a process, file descriptor 0. This card shows its role in “Shell fundamentals” and a safe diagnostic path.
Open learning card →Pipe — Shell fundamentals
Pipe: A connection feeding one process's standard output into the next process's input. This card shows its role in “Shell fundamentals” and a safe diagnostic path.
Open learning card →Redirection — Shell fundamentals
Redirection: A shell instruction connecting input or output streams to files or other destinations. This card shows its role in “Shell fundamentals” and a safe diagnostic path.
Open learning card →Environment variable — Shell fundamentals
Environment variable: A named string value inherited by child processes. This card shows its role in “Shell fundamentals” and a safe diagnostic path.
Open learning card →Shell variable — Shell fundamentals
Shell variable: A named value in the current shell state that is not automatically inherited. This card shows its role in “Shell fundamentals” and a safe diagnostic path.
Open learning card →Quoting — Shell fundamentals
Quoting: Shell syntax controlling spaces or expansions within an argument. This card shows its role in “Shell fundamentals” and a safe diagnostic path.
Open learning card →Escaping — Shell fundamentals
Escaping: Neutralising the special meaning of an individual character. This card shows its role in “Shell fundamentals” and a safe diagnostic path.
Open learning card →Wildcard — Shell fundamentals
Wildcard: A placeholder character such as `*` or `?` in a matching pattern. This card shows its role in “Shell fundamentals” and a safe diagnostic path.
Open learning card →Command history — Shell fundamentals
Command history: The sequence of previously entered commands stored by the shell. This card shows its role in “Shell fundamentals” and a safe diagnostic path.
Open learning card →Tab completion — Shell fundamentals
Tab completion: The shell feature that completes names and options after pressing Tab. This card shows its role in “Shell fundamentals” and a safe diagnostic path.
Open learning card →pwd — Shell fundamentals
pwd: The shell command that prints the absolute path of the working directory. This card shows its role in “Shell fundamentals” and a safe diagnostic path.
Open learning card →cd — Shell fundamentals
cd: The shell command that changes the current shell's working directory. This card shows its role in “Shell fundamentals” and a safe diagnostic path.
Open learning card →ls — Shell fundamentals
ls: The command for listing directory entries and metadata. This card shows its role in “Shell fundamentals” and a safe diagnostic path.
Open learning card →mkdir — Shell fundamentals
mkdir: The command for creating one or more directories. This card shows its role in “Shell fundamentals” and a safe diagnostic path.
Open learning card →cp — Shell fundamentals
cp: The command for copying files or directory trees. This card shows its role in “Shell fundamentals” and a safe diagnostic path.
Open learning card →mv — Shell fundamentals
mv: The command for moving or renaming files. This card shows its role in “Shell fundamentals” and a safe diagnostic path.
Open learning card →rm — Shell fundamentals
rm: The command for removing directory entries without a recycle bin. This card shows its role in “Shell fundamentals” and a safe diagnostic path.
Open learning card →find — Shell fundamentals
find: A tool that searches directory trees by file properties. This card shows its role in “Shell fundamentals” and a safe diagnostic path.
Open learning card →grep — Shell fundamentals
grep: A tool that filters text lines using regular expressions. This card shows its role in “Shell fundamentals” and a safe diagnostic path.
Open learning card →head — Shell fundamentals
head: A tool that outputs the beginning of a text stream. This card shows its role in “Shell fundamentals” and a safe diagnostic path.
Open learning card →tail — Shell fundamentals
tail: A tool that outputs or follows the end of a text stream. This card shows its role in “Shell fundamentals” and a safe diagnostic path.
Open learning card →less — Shell fundamentals
less: An interactive pager for navigating long text output. This card shows its role in “Shell fundamentals” and a safe diagnostic path.
Open learning card →Level 0 · Module 4Users, permissions, and processesFundamentals, operations, and troubleshooting for Users, permissions, and processes.32 terms
User account — Users, permissions, and processes
User account: A stored user identity with a login name, identifier, and assigned permissions. This card shows its role in “Users, permissions, and processes” and a safe diagnostic path.
Open learning card →System user — Users, permissions, and processes
System user: A usually non-interactive account under which a service runs with limited privileges. This card shows its role in “Users, permissions, and processes” and a safe diagnostic path.
Open learning card →UID — Users, permissions, and processes
UID: The numeric user identifier the kernel uses instead of the name for permission checks. This card shows its role in “Users, permissions, and processes” and a safe diagnostic path.
Open learning card →GID — Users, permissions, and processes
GID: The numeric identifier of a Unix group used for shared access permissions. This card shows its role in “Users, permissions, and processes” and a safe diagnostic path.
Open learning card →Root user — Users, permissions, and processes
Root user: The Unix account with unrestricted system privileges. This card shows its role in “Users, permissions, and processes” and a safe diagnostic path.
Open learning card →sudo — Users, permissions, and processes
sudo: A tool for controlled execution of individual commands under another identity. This card shows its role in “Users, permissions, and processes” and a safe diagnostic path.
Open learning card →Least privilege — Users, permissions, and processes
Least privilege: The principle of granting an account or process only the privileges required for its task. This card shows its role in “Users, permissions, and processes” and a safe diagnostic path.
Open learning card →Process — Users, permissions, and processes
Process: A running program instance with its own address space and resources. This card shows its role in “Users, permissions, and processes” and a safe diagnostic path.
Open learning card →PID — Users, permissions, and processes
PID: The numeric identifier of a running process. This card shows its role in “Users, permissions, and processes” and a safe diagnostic path.
Open learning card →Parent process — Users, permissions, and processes
Parent process: The process that creates another process and can collect its status. This card shows its role in “Users, permissions, and processes” and a safe diagnostic path.
Open learning card →Child process — Users, permissions, and processes
Child process: A process started by a parent process and assigned its own PID. This card shows its role in “Users, permissions, and processes” and a safe diagnostic path.
Open learning card →Daemon — Users, permissions, and processes
Daemon: A long-running service process operating in the background. This card shows its role in “Users, permissions, and processes” and a safe diagnostic path.
Open learning card →Foreground process — Users, permissions, and processes
Foreground process: A process currently attached to the controlling terminal. This card shows its role in “Users, permissions, and processes” and a safe diagnostic path.
Open learning card →Background process — Users, permissions, and processes
Background process: A process that continues without owning the current terminal input. This card shows its role in “Users, permissions, and processes” and a safe diagnostic path.
Open learning card →Signal — Users, permissions, and processes
Signal: An asynchronous kernel notification informing a process about an event or control request. This card shows its role in “Users, permissions, and processes” and a safe diagnostic path.
Open learning card →SIGTERM — Users, permissions, and processes
SIGTERM: The catchable signal requesting graceful process termination. This card shows its role in “Users, permissions, and processes” and a safe diagnostic path.
Open learning card →SIGKILL — Users, permissions, and processes
SIGKILL: The uncatchable signal that immediately terminates a process. This card shows its role in “Users, permissions, and processes” and a safe diagnostic path.
Open learning card →Process state — Users, permissions, and processes
Process state: The current scheduler state of a process, such as running, sleeping, or exited. This card shows its role in “Users, permissions, and processes” and a safe diagnostic path.
Open learning card →Zombie process — Users, permissions, and processes
Zombie process: An exited process whose status has not yet been collected by its parent. This card shows its role in “Users, permissions, and processes” and a safe diagnostic path.
Open learning card →Process priority — Users, permissions, and processes
Process priority: The weighting used by the scheduler when distributing CPU time among processes. This card shows its role in “Users, permissions, and processes” and a safe diagnostic path.
Open learning card →Nice value — Users, permissions, and processes
Nice value: A Unix value influencing CPU priority, with larger values receiving less preference. This card shows its role in “Users, permissions, and processes” and a safe diagnostic path.
Open learning card →Resource limit — Users, permissions, and processes
Resource limit: A kernel-enforced ceiling for resources such as memory, processes, or open files. This card shows its role in “Users, permissions, and processes” and a safe diagnostic path.
Open learning card →Open file — Users, permissions, and processes
Open file: A file or other I/O endpoint used by a process through a descriptor. This card shows its role in “Users, permissions, and processes” and a safe diagnostic path.
Open learning card →File descriptor — Users, permissions, and processes
File descriptor: A small process-local number referring to an open file, pipe, or socket. This card shows its role in “Users, permissions, and processes” and a safe diagnostic path.
Open learning card →User group — Users, permissions, and processes
User group: A collection of user accounts to which shared permissions are assigned. This card shows its role in “Users, permissions, and processes” and a safe diagnostic path.
Open learning card →Ownership change — Users, permissions, and processes
Ownership change: Changing the user or group assignment of a file-system object. This card shows its role in “Users, permissions, and processes” and a safe diagnostic path.
Open learning card →chmod — Users, permissions, and processes
chmod: The Unix command for changing file permission bits. This card shows its role in “Users, permissions, and processes” and a safe diagnostic path.
Open learning card →chown — Users, permissions, and processes
chown: The Unix command for changing owner and group. This card shows its role in “Users, permissions, and processes” and a safe diagnostic path.
Open learning card →ps — Users, permissions, and processes
ps: The tool for taking a snapshot of running processes and their identifiers. This card shows its role in “Users, permissions, and processes” and a safe diagnostic path.
Open learning card →top — Users, permissions, and processes
top: An interactive real-time monitor for processes, CPU, and memory usage. This card shows its role in “Users, permissions, and processes” and a safe diagnostic path.
Open learning card →htop — Users, permissions, and processes
htop: An interactive visual process viewer with search and process controls. This card shows its role in “Users, permissions, and processes” and a safe diagnostic path.
Open learning card →kill — Users, permissions, and processes
kill: The command for sending a signal to a process or process group. This card shows its role in “Users, permissions, and processes” and a safe diagnostic path.
Open learning card →Level 0 · Module 5Networking fundamentalsFundamentals, operations, and troubleshooting for Networking fundamentals.32 terms
Network — Networking fundamentals
Network: Connected systems exchanging data through agreed protocols. This card shows its role in “Networking fundamentals” and a safe diagnostic path.
Open learning card →LAN — Networking fundamentals
LAN: A geographically limited local network. This card shows its role in “Networking fundamentals” and a safe diagnostic path.
Open learning card →WAN — Networking fundamentals
WAN: A network connecting remote local networks across larger distances. This card shows its role in “Networking fundamentals” and a safe diagnostic path.
Open learning card →Internet — Networking fundamentals
Internet: The global interconnected network based on the Internet protocol suite. This card shows its role in “Networking fundamentals” and a safe diagnostic path.
Open learning card →IP address — Networking fundamentals
IP address: A logical address by which an interface is reachable in an IP network. This card shows its role in “Networking fundamentals” and a safe diagnostic path.
Open learning card →IPv4 — Networking fundamentals
IPv4: The IP version using 32-bit addresses. This card shows its role in “Networking fundamentals” and a safe diagnostic path.
Open learning card →IPv6 — Networking fundamentals
IPv6: The IP version using 128-bit addresses and a vastly larger address space. This card shows its role in “Networking fundamentals” and a safe diagnostic path.
Open learning card →Subnet — Networking fundamentals
Subnet: A contiguous IP address range sharing a network prefix. This card shows its role in “Networking fundamentals” and a safe diagnostic path.
Open learning card →Subnet mask — Networking fundamentals
Subnet mask: An IPv4 mask separating the network prefix from the host portion of an address. This card shows its role in “Networking fundamentals” and a safe diagnostic path.
Open learning card →Default gateway — Networking fundamentals
Default gateway: The router to which packets for destinations outside the local network are sent. This card shows its role in “Networking fundamentals” and a safe diagnostic path.
Open learning card →Router — Networking fundamentals
Router: A device or process that forwards packets between IP networks. This card shows its role in “Networking fundamentals” and a safe diagnostic path.
Open learning card →Switch — Networking fundamentals
Switch: A Layer 2 device forwarding Ethernet frames based on MAC addresses. This card shows its role in “Networking fundamentals” and a safe diagnostic path.
Open learning card →MAC address — Networking fundamentals
MAC address: An identifier of a network interface on the local Ethernet layer. This card shows its role in “Networking fundamentals” and a safe diagnostic path.
Open learning card →Port — Networking fundamentals
Port: A 16-bit number mapping TCP or UDP traffic to a service. This card shows its role in “Networking fundamentals” and a safe diagnostic path.
Open learning card →TCP — Networking fundamentals
TCP: A connection-oriented transport protocol providing ordered, acknowledged delivery. This card shows its role in “Networking fundamentals” and a safe diagnostic path.
Open learning card →UDP — Networking fundamentals
UDP: A connectionless transport protocol without delivery or ordering guarantees. This card shows its role in “Networking fundamentals” and a safe diagnostic path.
Open learning card →Socket — Networking fundamentals
Socket: An operating-system endpoint for network communication. This card shows its role in “Networking fundamentals” and a safe diagnostic path.
Open learning card →Connection — Networking fundamentals
Connection: The stateful communication channel between two network endpoints. This card shows its role in “Networking fundamentals” and a safe diagnostic path.
Open learning card →Packet — Networking fundamentals
Packet: A bounded unit of data with headers and payload transmitted through a network. This card shows its role in “Networking fundamentals” and a safe diagnostic path.
Open learning card →Bandwidth — Networking fundamentals
Bandwidth: The theoretical or practical amount of data transferable per unit time. This card shows its role in “Networking fundamentals” and a safe diagnostic path.
Open learning card →Latency — Networking fundamentals
Latency: The delay between sending and observing a response. This card shows its role in “Networking fundamentals” and a safe diagnostic path.
Open learning card →Packet loss — Networking fundamentals
Packet loss: The failure of individual transmitted packets to reach their destination. This card shows its role in “Networking fundamentals” and a safe diagnostic path.
Open learning card →Loopback — Networking fundamentals
Loopback: A virtual network interface whose traffic remains within the local host. This card shows its role in “Networking fundamentals” and a safe diagnostic path.
Open learning card →localhost — Networking fundamentals
localhost: The name conventionally resolving to the local loopback address. This card shows its role in “Networking fundamentals” and a safe diagnostic path.
Open learning card →Private IP address — Networking fundamentals
Private IP address: An address from reserved ranges that is not globally routed on the Internet. This card shows its role in “Networking fundamentals” and a safe diagnostic path.
Open learning card →Public IP address — Networking fundamentals
Public IP address: An IP address that is globally routable on the Internet. This card shows its role in “Networking fundamentals” and a safe diagnostic path.
Open learning card →NAT — Networking fundamentals
NAT: Rewriting IP addresses or ports at a network boundary. This card shows its role in “Networking fundamentals” and a safe diagnostic path.
Open learning card →Firewall — Networking fundamentals
Firewall: A rule-enforcement point that permits or drops network traffic by its properties. This card shows its role in “Networking fundamentals” and a safe diagnostic path.
Open learning card →Inbound traffic — Networking fundamentals
Inbound traffic: Network traffic arriving at a host or service from outside. This card shows its role in “Networking fundamentals” and a safe diagnostic path.
Open learning card →Outbound traffic — Networking fundamentals
Outbound traffic: Network traffic sent outward by a host or service. This card shows its role in “Networking fundamentals” and a safe diagnostic path.
Open learning card →ping — Networking fundamentals
ping: A diagnostic tool sending ICMP echo requests and measuring response times. This card shows its role in “Networking fundamentals” and a safe diagnostic path.
Open learning card →traceroute — Networking fundamentals
traceroute: A diagnostic tool revealing router hops toward a destination. This card shows its role in “Networking fundamentals” and a safe diagnostic path.
Open learning card →Level 0 · Module 6Web fundamentalsFundamentals, operations, and troubleshooting for Web fundamentals.32 terms
Web browser — Web fundamentals
Web browser: A client that retrieves web resources over HTTP, renders HTML, and executes scripts. This card shows its role in “Web fundamentals” and a safe diagnostic path.
Open learning card →Website — Web fundamentals
Website: A related collection of web resources under a common origin. This card shows its role in “Web fundamentals” and a safe diagnostic path.
Open learning card →Web server — Web fundamentals
Web server: Software that accepts HTTP requests and returns static or dynamic responses. This card shows its role in “Web fundamentals” and a safe diagnostic path.
Open learning card →URL — Web fundamentals
URL: A URI describing the location of and access method for a resource. This card shows its role in “Web fundamentals” and a safe diagnostic path.
Open learning card →URI — Web fundamentals
URI: A string that uniquely identifies a resource. This card shows its role in “Web fundamentals” and a safe diagnostic path.
Open learning card →Scheme — Web fundamentals
Scheme: The leading URL component such as `https` that specifies access protocol and semantics. This card shows its role in “Web fundamentals” and a safe diagnostic path.
Open learning card →Host — Web fundamentals
Host: The operating system or machine on which a process or virtual environment runs. This card shows its role in “Web fundamentals” and a safe diagnostic path.
Open learning card →Domain — Web fundamentals
Domain: A hierarchical DNS name that makes services and resources addressable. This card shows its role in “Web fundamentals” and a safe diagnostic path.
Open learning card →Subdomain — Web fundamentals
Subdomain: A subordinate namespace to the left of a parent domain. This card shows its role in “Web fundamentals” and a safe diagnostic path.
Open learning card →Path — Web fundamentals
Path: The URL component identifying a resource within an origin. This card shows its role in “Web fundamentals” and a safe diagnostic path.
Open learning card →Query parameter — Web fundamentals
Query parameter: A named key-value pair after `?` that parameterises a request. This card shows its role in “Web fundamentals” and a safe diagnostic path.
Open learning card →Fragment — Web fundamentals
Fragment: The URL component after `#` used locally by the client for navigation. This card shows its role in “Web fundamentals” and a safe diagnostic path.
Open learning card →HTTP — Web fundamentals
HTTP: A stateless request-response protocol for web resources. This card shows its role in “Web fundamentals” and a safe diagnostic path.
Open learning card →HTTPS — Web fundamentals
HTTPS: HTTP carried inside an authenticated and encrypted TLS connection. This card shows its role in “Web fundamentals” and a safe diagnostic path.
Open learning card →HTTP request — Web fundamentals
HTTP request: A client message containing a method, target, headers, and optional body. This card shows its role in “Web fundamentals” and a safe diagnostic path.
Open learning card →HTTP response — Web fundamentals
HTTP response: The server reply containing a status code, headers, and optional payload. This card shows its role in “Web fundamentals” and a safe diagnostic path.
Open learning card →HTTP method — Web fundamentals
HTTP method: The verb of an HTTP request that identifies the desired operation. This card shows its role in “Web fundamentals” and a safe diagnostic path.
Open learning card →GET — Web fundamentals
GET: The safe HTTP method for retrieving a resource representation. This card shows its role in “Web fundamentals” and a safe diagnostic path.
Open learning card →POST — Web fundamentals
POST: The HTTP method for submitting data for server-side processing. This card shows its role in “Web fundamentals” and a safe diagnostic path.
Open learning card →PUT — Web fundamentals
PUT: The idempotent HTTP method for fully replacing a target resource. This card shows its role in “Web fundamentals” and a safe diagnostic path.
Open learning card →PATCH — Web fundamentals
PATCH: The HTTP method for partially modifying a resource. This card shows its role in “Web fundamentals” and a safe diagnostic path.
Open learning card →DELETE — Web fundamentals
DELETE: The idempotent HTTP method for removing a resource. This card shows its role in “Web fundamentals” and a safe diagnostic path.
Open learning card →HTTP status code — Web fundamentals
HTTP status code: A three-digit number classifying success, redirection, or failure of an HTTP response. This card shows its role in “Web fundamentals” and a safe diagnostic path.
Open learning card →Header — Web fundamentals
Header: A named metadata field in an HTTP message. This card shows its role in “Web fundamentals” and a safe diagnostic path.
Open learning card →Body — Web fundamentals
Body: The optional payload of an HTTP request or response. This card shows its role in “Web fundamentals” and a safe diagnostic path.
Open learning card →Content-Type — Web fundamentals
Content-Type: The HTTP header specifying the media format and optional character encoding of a body. This card shows its role in “Web fundamentals” and a safe diagnostic path.
Open learning card →User-Agent — Web fundamentals
User-Agent: A client identifier in an HTTP header that may describe software and platform. This card shows its role in “Web fundamentals” and a safe diagnostic path.
Open learning card →Cookie — Web fundamentals
Cookie: A small value stored and sent by the browser for an origin. This card shows its role in “Web fundamentals” and a safe diagnostic path.
Open learning card →Cache — Web fundamentals
Cache: A fast temporary store avoiding repeated computation or transfer. This card shows its role in “Web fundamentals” and a safe diagnostic path.
Open learning card →Redirect — Web fundamentals
Redirect: An HTTP response directing the client to another target. This card shows its role in “Web fundamentals” and a safe diagnostic path.
Open learning card →Origin — Web fundamentals
Origin: The combination of URL scheme, host, and port forming a web security boundary. This card shows its role in “Web fundamentals” and a safe diagnostic path.
Open learning card →Same-origin policy — Web fundamentals
Same-origin policy: The browser rule limiting script access across different origins. This card shows its role in “Web fundamentals” and a safe diagnostic path.
Open learning card →Level 0 · Module 7Data and configuration formatsFundamentals, operations, and troubleshooting for Data and configuration formats.32 terms
Plain text — Data and configuration formats
Plain text: Unformatted character content without binary structure or markup semantics. This card shows its role in “Data and configuration formats” and a safe diagnostic path.
Open learning card →JSON — Data and configuration formats
JSON: A text format for objects, arrays, and primitive values. This card shows its role in “Data and configuration formats” and a safe diagnostic path.
Open learning card →YAML — Data and configuration formats
YAML: An indentation-sensitive, human-readable data format commonly used for configuration. This card shows its role in “Data and configuration formats” and a safe diagnostic path.
Open learning card →TOML — Data and configuration formats
TOML: A configuration format using typed key-values and tables. This card shows its role in “Data and configuration formats” and a safe diagnostic path.
Open learning card →XML — Data and configuration formats
XML: A textual tree format with nested elements and attributes. This card shows its role in “Data and configuration formats” and a safe diagnostic path.
Open learning card →CSV — Data and configuration formats
CSV: A row-oriented tabular format with delimited field values. This card shows its role in “Data and configuration formats” and a safe diagnostic path.
Open learning card →Markdown — Data and configuration formats
Markdown: A lightweight markup language for structured text. This card shows its role in “Data and configuration formats” and a safe diagnostic path.
Open learning card →HTML — Data and configuration formats
HTML: The markup language describing a web page's structure and semantics. This card shows its role in “Data and configuration formats” and a safe diagnostic path.
Open learning card →MIME type — Data and configuration formats
MIME type: A standardised label for content format, such as `image/png`. This card shows its role in “Data and configuration formats” and a safe diagnostic path.
Open learning card →UTF-8 — Data and configuration formats
UTF-8: A variable-length Unicode character encoding using one to four bytes. This card shows its role in “Data and configuration formats” and a safe diagnostic path.
Open learning card →Unicode — Data and configuration formats
Unicode: The standard assigning abstract code points to writing-system characters. This card shows its role in “Data and configuration formats” and a safe diagnostic path.
Open learning card →Line ending — Data and configuration formats
Line ending: The character sequence marking the end of a text line, such as LF or CRLF. This card shows its role in “Data and configuration formats” and a safe diagnostic path.
Open learning card →Escape sequence — Data and configuration formats
Escape sequence: A character sequence encoding a special character or control behaviour. This card shows its role in “Data and configuration formats” and a safe diagnostic path.
Open learning card →Key-value pair — Data and configuration formats
Key-value pair: A named association from a key to one value. This card shows its role in “Data and configuration formats” and a safe diagnostic path.
Open learning card →Object — Data and configuration formats
Object: A structured collection of named properties. This card shows its role in “Data and configuration formats” and a safe diagnostic path.
Open learning card →Array — Data and configuration formats
Array: An ordered list of zero or more values. This card shows its role in “Data and configuration formats” and a safe diagnostic path.
Open learning card →Boolean — Data and configuration formats
Boolean: A data type with the two truth values true and false. This card shows its role in “Data and configuration formats” and a safe diagnostic path.
Open learning card →Null value — Data and configuration formats
Null value: An explicit value representing the absence of a value. This card shows its role in “Data and configuration formats” and a safe diagnostic path.
Open learning card →Number — Data and configuration formats
Number: A numeric data value that may be integral or decimal depending on the format. This card shows its role in “Data and configuration formats” and a safe diagnostic path.
Open learning card →String — Data and configuration formats
String: An ordered sequence of characters. This card shows its role in “Data and configuration formats” and a safe diagnostic path.
Open learning card →Schema — Data and configuration formats
Schema: A machine-checkable description of allowed data structure and types. This card shows its role in “Data and configuration formats” and a safe diagnostic path.
Open learning card →Serialization — Data and configuration formats
Serialization: Converting a runtime value into a storable or transferable format. This card shows its role in “Data and configuration formats” and a safe diagnostic path.
Open learning card →Deserialization — Data and configuration formats
Deserialization: Reconstructing a runtime value from serialised data. This card shows its role in “Data and configuration formats” and a safe diagnostic path.
Open learning card →Parser — Data and configuration formats
Parser: Software that turns input text into structure according to a grammar. This card shows its role in “Data and configuration formats” and a safe diagnostic path.
Open learning card →Syntax error — Data and configuration formats
Syntax error: Input that violates the grammar of the format being used. This card shows its role in “Data and configuration formats” and a safe diagnostic path.
Open learning card →Indentation — Data and configuration formats
Indentation: Leading whitespace that controls readability or, in YAML, nesting. This card shows its role in “Data and configuration formats” and a safe diagnostic path.
Open learning card →Comment — Data and configuration formats
Comment: Human-readable text ignored by a parser according to the format rules. This card shows its role in “Data and configuration formats” and a safe diagnostic path.
Open learning card →Duplicate key — Data and configuration formats
Duplicate key: Multiple occurrences of the same key in an object or mapping. This card shows its role in “Data and configuration formats” and a safe diagnostic path.
Open learning card →.env file — Data and configuration formats
.env file: A text file of environment variables loaded into processes by a tool. This card shows its role in “Data and configuration formats” and a safe diagnostic path.
Open learning card →Secret — Data and configuration formats
Secret: A confidential value such as a password, key, or token. This card shows its role in “Data and configuration formats” and a safe diagnostic path.
Open learning card →Placeholder — Data and configuration formats
Placeholder: A recognisable substitute marker to be replaced with a real value before use. This card shows its role in “Data and configuration formats” and a safe diagnostic path.
Open learning card →Default value — Data and configuration formats
Default value: The value used automatically when no explicit value is supplied. This card shows its role in “Data and configuration formats” and a safe diagnostic path.
Open learning card →Level 0 · Module 8Systematic debuggingFundamentals, operations, and troubleshooting for Systematic debugging.32 terms
Failure symptom — Systematic debugging
Failure symptom: The observable effect of a failure without yet claiming its cause. This card shows its role in “Systematic debugging” and a safe diagnostic path.
Open learning card →Error message — Systematic debugging
Error message: Diagnostic output describing the type, location, or identifier of an error. This card shows its role in “Systematic debugging” and a safe diagnostic path.
Open learning card →Reproduction — Systematic debugging
Reproduction: A sequence of steps that triggers the same failure again. This card shows its role in “Systematic debugging” and a safe diagnostic path.
Open learning card →Minimal reproduction — Systematic debugging
Minimal reproduction: The smallest reliable set of inputs and steps that triggers a failure. This card shows its role in “Systematic debugging” and a safe diagnostic path.
Open learning card →Hypothesis — Systematic debugging
Hypothesis: A testable proposition about a cause or behaviour. This card shows its role in “Systematic debugging” and a safe diagnostic path.
Open learning card →Root cause — Systematic debugging
Root cause: The underlying cause whose correction permanently removes the failure. This card shows its role in “Systematic debugging” and a safe diagnostic path.
Open learning card →Symptom — Systematic debugging
Symptom: A measurable or visible sign of a problem. This card shows its role in “Systematic debugging” and a safe diagnostic path.
Open learning card →Correlation — Systematic debugging
Correlation: Co-occurrence of two observations without a proven cause-and-effect relationship. This card shows its role in “Systematic debugging” and a safe diagnostic path.
Open learning card →Causation — Systematic debugging
Causation: A demonstrated cause-and-effect relationship between a change and an outcome. This card shows its role in “Systematic debugging” and a safe diagnostic path.
Open learning card →Log analysis — Systematic debugging
Log analysis: Examining log messages by time and content to diagnose failures. This card shows its role in “Systematic debugging” and a safe diagnostic path.
Open learning card →Timestamp — Systematic debugging
Timestamp: A time value locating an event in logs or measurements. This card shows its role in “Systematic debugging” and a safe diagnostic path.
Open learning card →Stack trace — Systematic debugging
Stack trace: The chain of function or method calls at the time of a failure. This card shows its role in “Systematic debugging” and a safe diagnostic path.
Open learning card →Warning — Systematic debugging
Warning: A message about an unusual condition that does not necessarily stop execution. This card shows its role in “Systematic debugging” and a safe diagnostic path.
Open learning card →Error — Systematic debugging
Error: A condition in which a requested operation did not complete correctly. This card shows its role in “Systematic debugging” and a safe diagnostic path.
Open learning card →Debug level — Systematic debugging
Debug level: A highly verbose log level exposing internal state for diagnosis. This card shows its role in “Systematic debugging” and a safe diagnostic path.
Open learning card →Info level — Systematic debugging
Info level: A log level for normal, relevant operational events. This card shows its role in “Systematic debugging” and a safe diagnostic path.
Open learning card →Health check — Systematic debugging
Health check: A repeatable test of the minimum required service state. This card shows its role in “Systematic debugging” and a safe diagnostic path.
Open learning card →Smoke test — Systematic debugging
Smoke test: A brief test of core functions after startup or a change. This card shows its role in “Systematic debugging” and a safe diagnostic path.
Open learning card →Integration test — Systematic debugging
Integration test: A test exercising real interfaces between multiple components. This card shows its role in “Systematic debugging” and a safe diagnostic path.
Open learning card →Regression test — Systematic debugging
Regression test: A test detecting recurrence of a previous defect. This card shows its role in “Systematic debugging” and a safe diagnostic path.
Open learning card →Expected state — Systematic debugging
Expected state: The documented state a system or test is supposed to reach. This card shows its role in “Systematic debugging” and a safe diagnostic path.
Open learning card →Actual state — Systematic debugging
Actual state: The state actually observed in a system or test. This card shows its role in “Systematic debugging” and a safe diagnostic path.
Open learning card →Differential test — Systematic debugging
Differential test: A comparison of the same input across two versions or implementations. This card shows its role in “Systematic debugging” and a safe diagnostic path.
Open learning card →Configuration check — Systematic debugging
Configuration check: Checking that settings exist, are syntactically valid, and take effect. This card shows its role in “Systematic debugging” and a safe diagnostic path.
Open learning card →Syntax check — Systematic debugging
Syntax check: A check for grammar errors without fully executing the program. This card shows its role in “Systematic debugging” and a safe diagnostic path.
Open learning card →Network check — Systematic debugging
Network check: A layered check of name resolution, route, port, and application response. This card shows its role in “Systematic debugging” and a safe diagnostic path.
Open learning card →Permission check — Systematic debugging
Permission check: Checking effective identity and access permissions for a resource. This card shows its role in “Systematic debugging” and a safe diagnostic path.
Open learning card →Storage check — Systematic debugging
Storage check: Checking a storage target for mounting, free space, inodes, and writability. This card shows its role in “Systematic debugging” and a safe diagnostic path.
Open learning card →Resource check — Systematic debugging
Resource check: Checking whether CPU, RAM, storage, or GPU meets a service requirement. This card shows its role in “Systematic debugging” and a safe diagnostic path.
Open learning card →Rollback — Systematic debugging
Rollback: Returning to a previously known working state. This card shows its role in “Systematic debugging” and a safe diagnostic path.
Open learning card →Change history — Systematic debugging
Change history: A chronological record of relevant configuration and software changes. This card shows its role in “Systematic debugging” and a safe diagnostic path.
Open learning card →Root cause analysis — Systematic debugging
Root cause analysis: A structured investigation of symptom, cause, correction, and prevention. This card shows its role in “Systematic debugging” and a safe diagnostic path.
Open learning card →Level 1 · Module 9Linux services and packagesFundamentals, operations, and troubleshooting for Linux services and packages.32 terms
Package manager — Linux services and packages
Package manager: A tool for installing, upgrading, and removing packages with dependencies. This card shows its role in “Linux services and packages” and a safe diagnostic path.
Open learning card →APT — Linux services and packages
APT: The package-management interface for Debian-based systems. This card shows its role in “Linux services and packages” and a safe diagnostic path.
Open learning card →Package source — Linux services and packages
Package source: A configured location from which packages and metadata are obtained. This card shows its role in “Linux services and packages” and a safe diagnostic path.
Open learning card →Repository — Linux services and packages
Repository: A source of versioned packages and their metadata. This card shows its role in “Linux services and packages” and a safe diagnostic path.
Open learning card →Package index — Linux services and packages
Package index: A local catalogue of available package names, versions, and dependencies. This card shows its role in “Linux services and packages” and a safe diagnostic path.
Open learning card →Package version — Linux services and packages
Package version: An identifier for a particular published revision of a package. This card shows its role in “Linux services and packages” and a safe diagnostic path.
Open learning card →Dependency — Linux services and packages
Dependency: A component required by another piece of software to function. This card shows its role in “Linux services and packages” and a safe diagnostic path.
Open learning card →Transitive dependency — Linux services and packages
Transitive dependency: An indirect dependency required by a direct dependency. This card shows its role in “Linux services and packages” and a safe diagnostic path.
Open learning card →Installation — Linux services and packages
Installation: Copying and registering software for use on a system. This card shows its role in “Linux services and packages” and a safe diagnostic path.
Open learning card →Uninstallation — Linux services and packages
Uninstallation: Controlled removal of installed software and its registration. This card shows its role in “Linux services and packages” and a safe diagnostic path.
Open learning card →Upgrade — Linux services and packages
Upgrade: Moving to a newer software version while retaining intended data. This card shows its role in “Linux services and packages” and a safe diagnostic path.
Open learning card →Security update — Linux services and packages
Security update: An update that fixes known security vulnerabilities. This card shows its role in “Linux services and packages” and a safe diagnostic path.
Open learning card →Version pinning — Linux services and packages
Version pinning: Fixing a concrete version so upgrades do not change it unexpectedly. This card shows its role in “Linux services and packages” and a safe diagnostic path.
Open learning card →systemd — Linux services and packages
systemd: The common Linux service manager and init process. This card shows its role in “Linux services and packages” and a safe diagnostic path.
Open learning card →Unit — Linux services and packages
Unit: A resource definition managed by systemd. This card shows its role in “Linux services and packages” and a safe diagnostic path.
Open learning card →Service unit — Linux services and packages
Service unit: A systemd file describing service startup, process supervision, and dependencies. This card shows its role in “Linux services and packages” and a safe diagnostic path.
Open learning card →Timer unit — Linux services and packages
Timer unit: A systemd file activating another unit at times or intervals. This card shows its role in “Linux services and packages” and a safe diagnostic path.
Open learning card →Target unit — Linux services and packages
Target unit: A systemd grouping unit used to synchronise multiple units toward a target state. This card shows its role in “Linux services and packages” and a safe diagnostic path.
Open learning card →Service status — Linux services and packages
Service status: The load, active, and failure state reported by systemd for a service. This card shows its role in “Linux services and packages” and a safe diagnostic path.
Open learning card →Service start — Linux services and packages
Service start: Instructing the service manager to start an inactive service. This card shows its role in “Linux services and packages” and a safe diagnostic path.
Open learning card →Service stop — Linux services and packages
Service stop: Controlled termination of a running service by the service manager. This card shows its role in “Linux services and packages” and a safe diagnostic path.
Open learning card →Service restart — Linux services and packages
Service restart: Stopping and then starting a service again. This card shows its role in “Linux services and packages” and a safe diagnostic path.
Open learning card →Service autostart — Linux services and packages
Service autostart: Enabling a service to start automatically at a boot target. This card shows its role in “Linux services and packages” and a safe diagnostic path.
Open learning card →System journal — Linux services and packages
System journal: The structured, centrally queried log store maintained by systemd-journald. This card shows its role in “Linux services and packages” and a safe diagnostic path.
Open learning card →journalctl — Linux services and packages
journalctl: The tool for querying the structured systemd journal. This card shows its role in “Linux services and packages” and a safe diagnostic path.
Open learning card →systemctl — Linux services and packages
systemctl: The tool for controlling and inspecting systemd units. This card shows its role in “Linux services and packages” and a safe diagnostic path.
Open learning card →Boot process — Linux services and packages
Boot process: The sequence from loading the kernel to reaching requested system targets. This card shows its role in “Linux services and packages” and a safe diagnostic path.
Open learning card →EnvironmentFile — Linux services and packages
EnvironmentFile: A file of environment variables read by a systemd unit. This card shows its role in “Linux services and packages” and a safe diagnostic path.
Open learning card →ExecStart — Linux services and packages
ExecStart: The systemd directive containing the main command started for a service. This card shows its role in “Linux services and packages” and a safe diagnostic path.
Open learning card →Restart policy — Linux services and packages
Restart policy: The rule determining when a service manager restarts an exited process. This card shows its role in “Linux services and packages” and a safe diagnostic path.
Open learning card →Unit dependency — Linux services and packages
Unit dependency: A declared ordering or requirement relationship between systemd units. This card shows its role in “Linux services and packages” and a safe diagnostic path.
Open learning card →Load state — Linux services and packages
Load state: The systemd state indicating whether a unit file was found and loaded successfully. This card shows its role in “Linux services and packages” and a safe diagnostic path.
Open learning card →Level 1 · Module 10Storage and backupsFundamentals, operations, and troubleshooting for Storage and backups.32 terms
Block device — Storage and backups
Block device: A storage device exposing data in addressable blocks. This card shows its role in “Storage and backups” and a safe diagnostic path.
Open learning card →Volume — Storage and backups
Volume: A logically usable storage region with its own lifecycle. This card shows its role in “Storage and backups” and a safe diagnostic path.
Open learning card →Bind mount — Storage and backups
Bind mount: Making an existing directory tree available at a second mount point. This card shows its role in “Storage and backups” and a safe diagnostic path.
Open learning card →Network share — Storage and backups
Network share: Shared file storage exposed through a network protocol. This card shows its role in “Storage and backups” and a safe diagnostic path.
Open learning card →SMB — Storage and backups
SMB: A network protocol for file and printer sharing, especially in Windows environments. This card shows its role in “Storage and backups” and a safe diagnostic path.
Open learning card →NFS — Storage and backups
NFS: A Unix-oriented protocol for remote file systems. This card shows its role in “Storage and backups” and a safe diagnostic path.
Open learning card →Storage capacity — Storage and backups
Storage capacity: The total amount of data a storage target can logically hold. This card shows its role in “Storage and backups” and a safe diagnostic path.
Open learning card →Disk usage — Storage and backups
Disk usage: The occupied portion of a file system, including metadata. This card shows its role in “Storage and backups” and a safe diagnostic path.
Open learning card →Reserved space — Storage and backups
Reserved space: Space retained by a file system for administration or privileged processes. This card shows its role in “Storage and backups” and a safe diagnostic path.
Open learning card →File system check — Storage and backups
File system check: A consistency check of a file system’s metadata and references. This card shows its role in “Storage and backups” and a safe diagnostic path.
Open learning card →Snapshot — Storage and backups
Snapshot: A point-in-time view of data, often implemented with copy-on-write. This card shows its role in “Storage and backups” and a safe diagnostic path.
Open learning card →Backup — Storage and backups
Backup: A separate copy from which lost or damaged data can be restored. This card shows its role in “Storage and backups” and a safe diagnostic path.
Open learning card →Full backup — Storage and backups
Full backup: A backup of all selected data independent of earlier backups. This card shows its role in “Storage and backups” and a safe diagnostic path.
Open learning card →Incremental backup — Storage and backups
Incremental backup: A backup of changes since the most recent backup of any type. This card shows its role in “Storage and backups” and a safe diagnostic path.
Open learning card →Differential backup — Storage and backups
Differential backup: A backup of all changes since the most recent full backup. This card shows its role in “Storage and backups” and a safe diagnostic path.
Open learning card →Restore — Storage and backups
Restore: Recovering backed-up data into a usable state. This card shows its role in “Storage and backups” and a safe diagnostic path.
Open learning card →Restore test — Storage and backups
Restore test: A controlled recovery attempt proving that a backup is usable. This card shows its role in “Storage and backups” and a safe diagnostic path.
Open learning card →Backup rotation — Storage and backups
Backup rotation: Rule-based retention and deletion of backups across time. This card shows its role in “Storage and backups” and a safe diagnostic path.
Open learning card →Retention period — Storage and backups
Retention period: The defined duration for which data or backups are retained. This card shows its role in “Storage and backups” and a safe diagnostic path.
Open learning card →Offsite backup — Storage and backups
Offsite backup: A backup stored in a geographically or administratively separate location. This card shows its role in “Storage and backups” and a safe diagnostic path.
Open learning card →3-2-1 backup rule — Storage and backups
3-2-1 backup rule: The recommendation for three copies on two media types with one offsite copy. This card shows its role in “Storage and backups” and a safe diagnostic path.
Open learning card →Checksum — Storage and backups
Checksum: A computed verification value for detecting unintended data changes. This card shows its role in “Storage and backups” and a safe diagnostic path.
Open learning card →SHA-256 — Storage and backups
SHA-256: A cryptographic hash function producing a 256-bit digest. This card shows its role in “Storage and backups” and a safe diagnostic path.
Open learning card →Data integrity — Storage and backups
Data integrity: The property that data remains complete and unintentionally unaltered. This card shows its role in “Storage and backups” and a safe diagnostic path.
Open learning card →Atomic write — Storage and backups
Atomic write: A write operation whose result becomes visible either completely or not at all. This card shows its role in “Storage and backups” and a safe diagnostic path.
Open learning card →File synchronization — Storage and backups
File synchronization: Reconciling two file sets based on their differences. This card shows its role in “Storage and backups” and a safe diagnostic path.
Open learning card →rsync — Storage and backups
rsync: A tool for efficiently synchronising file trees based on differences. This card shows its role in “Storage and backups” and a safe diagnostic path.
Open learning card →Archive — Storage and backups
Archive: A file bundling multiple files and metadata. This card shows its role in “Storage and backups” and a safe diagnostic path.
Open learning card →Compression — Storage and backups
Compression: Encoding data using less storage space. This card shows its role in “Storage and backups” and a safe diagnostic path.
Open learning card →tar — Storage and backups
tar: An archive format and tool bundling file trees with metadata. This card shows its role in “Storage and backups” and a safe diagnostic path.
Open learning card →Deletion deadline — Storage and backups
Deletion deadline: The defined time after which data should be removed automatically. This card shows its role in “Storage and backups” and a safe diagnostic path.
Open learning card →Data lifecycle — Storage and backups
Data lifecycle: The sequence of data creation, use, retention, and deletion. This card shows its role in “Storage and backups” and a safe diagnostic path.
Open learning card →Level 1 · Module 11DNS, TLS, CDN, and tunnelsFundamentals, operations, and troubleshooting for DNS, TLS, CDN, and tunnels.32 terms
DNS — DNS, TLS, CDN, and tunnels
DNS: The distributed system resolving domain names into resource data. This card shows its role in “DNS, TLS, CDN, and tunnels” and a safe diagnostic path.
Open learning card →DNS zone — DNS, TLS, CDN, and tunnels
DNS zone: An administratively managed portion of the DNS namespace. This card shows its role in “DNS, TLS, CDN, and tunnels” and a safe diagnostic path.
Open learning card →Resource record — DNS, TLS, CDN, and tunnels
Resource record: A typed DNS data record containing a name, value, and lifetime. This card shows its role in “DNS, TLS, CDN, and tunnels” and a safe diagnostic path.
Open learning card →A record — DNS, TLS, CDN, and tunnels
A record: A DNS record mapping a name to an IPv4 address. This card shows its role in “DNS, TLS, CDN, and tunnels” and a safe diagnostic path.
Open learning card →AAAA record — DNS, TLS, CDN, and tunnels
AAAA record: A DNS record mapping a name to an IPv6 address. This card shows its role in “DNS, TLS, CDN, and tunnels” and a safe diagnostic path.
Open learning card →CNAME record — DNS, TLS, CDN, and tunnels
CNAME record: A DNS alias pointing one name to another canonical name. This card shows its role in “DNS, TLS, CDN, and tunnels” and a safe diagnostic path.
Open learning card →TXT record — DNS, TLS, CDN, and tunnels
TXT record: A DNS record for text values, often used for verification or policy declarations. This card shows its role in “DNS, TLS, CDN, and tunnels” and a safe diagnostic path.
Open learning card →MX record — DNS, TLS, CDN, and tunnels
MX record: A DNS record naming responsible mail servers and their priorities. This card shows its role in “DNS, TLS, CDN, and tunnels” and a safe diagnostic path.
Open learning card →Name server — DNS, TLS, CDN, and tunnels
Name server: An authoritative or recursive service that answers DNS queries. This card shows its role in “DNS, TLS, CDN, and tunnels” and a safe diagnostic path.
Open learning card →Resolver — DNS, TLS, CDN, and tunnels
Resolver: A service answering DNS queries recursively or from cache. This card shows its role in “DNS, TLS, CDN, and tunnels” and a safe diagnostic path.
Open learning card →DNS cache — DNS, TLS, CDN, and tunnels
DNS cache: A cache of resolved DNS answers retained until their TTL expires. This card shows its role in “DNS, TLS, CDN, and tunnels” and a safe diagnostic path.
Open learning card →DNS TTL — DNS, TLS, CDN, and tunnels
DNS TTL: The permitted caching lifetime of a DNS record in seconds. This card shows its role in “DNS, TLS, CDN, and tunnels” and a safe diagnostic path.
Open learning card →DNS propagation — DNS, TLS, CDN, and tunnels
DNS propagation: The delayed visibility of changed DNS answers caused by distributed caches. This card shows its role in “DNS, TLS, CDN, and tunnels” and a safe diagnostic path.
Open learning card →Certificate — DNS, TLS, CDN, and tunnels
Certificate: A signed document binding a public key to names. This card shows its role in “DNS, TLS, CDN, and tunnels” and a safe diagnostic path.
Open learning card →Certificate authority — DNS, TLS, CDN, and tunnels
Certificate authority: A trust authority that validates identities and digitally signs certificates. This card shows its role in “DNS, TLS, CDN, and tunnels” and a safe diagnostic path.
Open learning card →Let's Encrypt — DNS, TLS, CDN, and tunnels
Let's Encrypt: A public automated certificate authority providing free TLS certificates. This card shows its role in “DNS, TLS, CDN, and tunnels” and a safe diagnostic path.
Open learning card →TLS — DNS, TLS, CDN, and tunnels
TLS: A protocol providing authenticated, confidential, integrity-protected connections. This card shows its role in “DNS, TLS, CDN, and tunnels” and a safe diagnostic path.
Open learning card →TLS handshake — DNS, TLS, CDN, and tunnels
TLS handshake: The setup of a TLS connection including negotiation, certificate validation, and key establishment. This card shows its role in “DNS, TLS, CDN, and tunnels” and a safe diagnostic path.
Open learning card →Public key — DNS, TLS, CDN, and tunnels
Public key: The shareable key component used for encryption or signature verification. This card shows its role in “DNS, TLS, CDN, and tunnels” and a safe diagnostic path.
Open learning card →Private key — DNS, TLS, CDN, and tunnels
Private key: The secret key component used for decryption or signature creation. This card shows its role in “DNS, TLS, CDN, and tunnels” and a safe diagnostic path.
Open learning card →Certificate chain — DNS, TLS, CDN, and tunnels
Certificate chain: The sequence from a server certificate through intermediates to a trusted root. This card shows its role in “DNS, TLS, CDN, and tunnels” and a safe diagnostic path.
Open learning card →SNI — DNS, TLS, CDN, and tunnels
SNI: The TLS extension through which a client states the requested hostname during the handshake. This card shows its role in “DNS, TLS, CDN, and tunnels” and a safe diagnostic path.
Open learning card →HSTS — DNS, TLS, CDN, and tunnels
HSTS: An HTTP header instructing browsers to use HTTPS exclusively for a period. This card shows its role in “DNS, TLS, CDN, and tunnels” and a safe diagnostic path.
Open learning card →CDN — DNS, TLS, CDN, and tunnels
CDN: A distributed network of edge servers delivering content closer to users. This card shows its role in “DNS, TLS, CDN, and tunnels” and a safe diagnostic path.
Open learning card →Reverse tunnel — DNS, TLS, CDN, and tunnels
Reverse tunnel: An internally initiated connection carrying controlled external access back inward. This card shows its role in “DNS, TLS, CDN, and tunnels” and a safe diagnostic path.
Open learning card →Cloudflare Tunnel — DNS, TLS, CDN, and tunnels
Cloudflare Tunnel: An outbound connection from `cloudflared` to Cloudflare’s edge for published origins. This card shows its role in “DNS, TLS, CDN, and tunnels” and a safe diagnostic path.
Open learning card →cloudflared — DNS, TLS, CDN, and tunnels
cloudflared: The agent establishing Cloudflare tunnels and forwarding to origin services. This card shows its role in “DNS, TLS, CDN, and tunnels” and a safe diagnostic path.
Open learning card →Tunnel token — DNS, TLS, CDN, and tunnels
Tunnel token: A confidential credential allowing a tunnel agent to join a tunnel configuration. This card shows its role in “DNS, TLS, CDN, and tunnels” and a safe diagnostic path.
Open learning card →Public hostname — DNS, TLS, CDN, and tunnels
Public hostname: The publicly resolvable DNS name through which a service is addressed. This card shows its role in “DNS, TLS, CDN, and tunnels” and a safe diagnostic path.
Open learning card →Origin service — DNS, TLS, CDN, and tunnels
Origin service: The internal origin service to which a proxy or tunnel forwards requests. This card shows its role in “DNS, TLS, CDN, and tunnels” and a safe diagnostic path.
Open learning card →Zero Trust — DNS, TLS, CDN, and tunnels
Zero Trust: An access model that trusts no network location by default and evaluates every request. This card shows its role in “DNS, TLS, CDN, and tunnels” and a safe diagnostic path.
Open learning card →Access policy — DNS, TLS, CDN, and tunnels
Access policy: A rule defining identities and conditions for permitted access. This card shows its role in “DNS, TLS, CDN, and tunnels” and a safe diagnostic path.
Open learning card →Level 1 · Module 12Docker fundamentalsFundamentals, operations, and troubleshooting for Docker fundamentals.32 terms
Container — Docker fundamentals
Container isolates a process with its own filesystem and network namespace. This card shows its role in “Docker fundamentals” and a safe diagnostic path.
Open learning card →Container image — Docker fundamentals
Container image provides the immutable filesystem and startup metadata for a container. This card shows its role in “Docker fundamentals” and a safe diagnostic path.
Open learning card →Image layer — Docker fundamentals
Image layer stores one immutable filesystem change inside an image. This card shows its role in “Docker fundamentals” and a safe diagnostic path.
Open learning card →Dockerfile — Docker fundamentals
Dockerfile reproducibly describes how Docker builds an image from instructions. This card shows its role in “Docker fundamentals” and a safe diagnostic path.
Open learning card →Build context — Docker fundamentals
Build context is the file set available to the Docker builder for COPY and ADD. This card shows its role in “Docker fundamentals” and a safe diagnostic path.
Open learning card →Base image — Docker fundamentals
Base image provides the immutable filesystem and startup metadata for a container. This card shows its role in “Docker fundamentals” and a safe diagnostic path.
Open learning card →Image tag — Docker fundamentals
Image tag is a human-readable and mutable reference to an image version. This card shows its role in “Docker fundamentals” and a safe diagnostic path.
Open learning card →Image digest — Docker fundamentals
Image digest identifies image content immutably through a cryptographic hash. This card shows its role in “Docker fundamentals” and a safe diagnostic path.
Open learning card →Container registry — Docker fundamentals
Container registry stores and distributes versioned container images. This card shows its role in “Docker fundamentals” and a safe diagnostic path.
Open learning card →Docker Hub — Docker fundamentals
Docker Hub stores and distributes versioned container images. This card shows its role in “Docker fundamentals” and a safe diagnostic path.
Open learning card →Container runtime — Docker fundamentals
Container runtime belongs to Docker's control path between a user command and a running container. This card shows its role in “Docker fundamentals” and a safe diagnostic path.
Open learning card →Docker Engine — Docker fundamentals
Docker Engine belongs to Docker's control path between a user command and a running container. This card shows its role in “Docker fundamentals” and a safe diagnostic path.
Open learning card →Docker daemon — Docker fundamentals
Docker daemon belongs to Docker's control path between a user command and a running container. This card shows its role in “Docker fundamentals” and a safe diagnostic path.
Open learning card →Docker CLI — Docker fundamentals
Docker CLI belongs to Docker's control path between a user command and a running container. This card shows its role in “Docker fundamentals” and a safe diagnostic path.
Open learning card →Container start — Docker fundamentals
Container start controls a defined transition in the container lifecycle. This card shows its role in “Docker fundamentals” and a safe diagnostic path.
Open learning card →Container stop — Docker fundamentals
Container stop controls a defined transition in the container lifecycle. This card shows its role in “Docker fundamentals” and a safe diagnostic path.
Open learning card →Container restart — Docker fundamentals
Container restart controls a defined transition in the container lifecycle. This card shows its role in “Docker fundamentals” and a safe diagnostic path.
Open learning card →Container log — Docker fundamentals
Container log contains standard output and standard error from the container's main process. This card shows its role in “Docker fundamentals” and a safe diagnostic path.
Open learning card →Port mapping — Docker fundamentals
Port mapping maps a reachable host port to a listening container port. This card shows its role in “Docker fundamentals” and a safe diagnostic path.
Open learning card →Container port — Docker fundamentals
Container port maps a reachable host port to a listening container port. This card shows its role in “Docker fundamentals” and a safe diagnostic path.
Open learning card →Host port — Docker fundamentals
Host port maps a reachable host port to a listening container port. This card shows its role in “Docker fundamentals” and a safe diagnostic path.
Open learning card →Docker network — Docker fundamentals
Docker network provides isolated name resolution and packet transport between containers. This card shows its role in “Docker fundamentals” and a safe diagnostic path.
Open learning card →Bridge network — Docker fundamentals
Bridge network provides isolated name resolution and packet transport between containers. This card shows its role in “Docker fundamentals” and a safe diagnostic path.
Open learning card →Overlay network — Docker fundamentals
Overlay network provides isolated name resolution and packet transport between containers. This card shows its role in “Docker fundamentals” and a safe diagnostic path.
Open learning card →Docker volume — Docker fundamentals
Docker volume attaches persistent or host-provided data to a container. This card shows its role in “Docker fundamentals” and a safe diagnostic path.
Open learning card →Bind mount — Docker fundamentals
Bind mount attaches persistent or host-provided data to a container. This card shows its role in “Docker fundamentals” and a safe diagnostic path.
Open learning card →Read-only mount — Docker fundamentals
Read-only mount attaches persistent or host-provided data to a container. This card shows its role in “Docker fundamentals” and a safe diagnostic path.
Open learning card →Entrypoint — Docker fundamentals
Entrypoint defines the program and arguments run as PID 1 in a container. This card shows its role in “Docker fundamentals” and a safe diagnostic path.
Open learning card →Command — Docker fundamentals
Command defines the program and arguments run as PID 1 in a container. This card shows its role in “Docker fundamentals” and a safe diagnostic path.
Open learning card →Container environment — Docker fundamentals
Container environment passes runtime configuration to the process as key-value pairs. This card shows its role in “Docker fundamentals” and a safe diagnostic path.
Open learning card →Health check — Docker fundamentals
Health check periodically verifies that a service is functional rather than merely started. This card shows its role in “Docker fundamentals” and a safe diagnostic path.
Open learning card →Restart policy — Docker fundamentals
Restart policy controls a defined transition in the container lifecycle. This card shows its role in “Docker fundamentals” and a safe diagnostic path.
Open learning card →Level 1 · Module 13Compose, Swarm, and PortainerFundamentals, operations, and troubleshooting for Compose, Swarm, and Portainer.32 terms
Docker Compose — Compose, Swarm, and Portainer
Docker Compose declaratively describes multiple container services as one application. This card shows its role in “Compose, Swarm, and Portainer” and a safe diagnostic path.
Open learning card →Compose file — Compose, Swarm, and Portainer
Compose file declaratively describes multiple container services as one application. This card shows its role in “Compose, Swarm, and Portainer” and a safe diagnostic path.
Open learning card →Compose service — Compose, Swarm, and Portainer
Compose service groups reproducibly configured containers inside a Compose namespace. This card shows its role in “Compose, Swarm, and Portainer” and a safe diagnostic path.
Open learning card →Compose project — Compose, Swarm, and Portainer
Compose project groups reproducibly configured containers inside a Compose namespace. This card shows its role in “Compose, Swarm, and Portainer” and a safe diagnostic path.
Open learning card →Docker Swarm — Compose, Swarm, and Portainer
Docker Swarm is part of the cluster that assigns service desired state to available nodes. This card shows its role in “Compose, Swarm, and Portainer” and a safe diagnostic path.
Open learning card →Swarm manager — Compose, Swarm, and Portainer
Swarm manager is part of the cluster that assigns service desired state to available nodes. This card shows its role in “Compose, Swarm, and Portainer” and a safe diagnostic path.
Open learning card →Swarm worker — Compose, Swarm, and Portainer
Swarm worker is part of the cluster that assigns service desired state to available nodes. This card shows its role in “Compose, Swarm, and Portainer” and a safe diagnostic path.
Open learning card →Swarm node — Compose, Swarm, and Portainer
Swarm node is part of the cluster that assigns service desired state to available nodes. This card shows its role in “Compose, Swarm, and Portainer” and a safe diagnostic path.
Open learning card →Stack — Compose, Swarm, and Portainer
Stack groups related Swarm services from a declarative stack file. This card shows its role in “Compose, Swarm, and Portainer” and a safe diagnostic path.
Open learning card →Swarm service — Compose, Swarm, and Portainer
Swarm service represents desired configuration, concrete execution, or replica state of a Swarm service. This card shows its role in “Compose, Swarm, and Portainer” and a safe diagnostic path.
Open learning card →Swarm task — Compose, Swarm, and Portainer
Swarm task represents desired configuration, concrete execution, or replica state of a Swarm service. This card shows its role in “Compose, Swarm, and Portainer” and a safe diagnostic path.
Open learning card →Replica — Compose, Swarm, and Portainer
Replica represents desired configuration, concrete execution, or replica state of a Swarm service. This card shows its role in “Compose, Swarm, and Portainer” and a safe diagnostic path.
Open learning card →Desired state — Compose, Swarm, and Portainer
Desired state represents desired configuration, concrete execution, or replica state of a Swarm service. This card shows its role in “Compose, Swarm, and Portainer” and a safe diagnostic path.
Open learning card →Current state — Compose, Swarm, and Portainer
Current state represents desired configuration, concrete execution, or replica state of a Swarm service. This card shows its role in “Compose, Swarm, and Portainer” and a safe diagnostic path.
Open learning card →Rolling update — Compose, Swarm, and Portainer
Rolling update controls the order, pace, and rollback behavior of a service update. This card shows its role in “Compose, Swarm, and Portainer” and a safe diagnostic path.
Open learning card →Update parallelism — Compose, Swarm, and Portainer
Update parallelism controls the order, pace, and rollback behavior of a service update. This card shows its role in “Compose, Swarm, and Portainer” and a safe diagnostic path.
Open learning card →Update delay — Compose, Swarm, and Portainer
Update delay controls the order, pace, and rollback behavior of a service update. This card shows its role in “Compose, Swarm, and Portainer” and a safe diagnostic path.
Open learning card →Rollback configuration — Compose, Swarm, and Portainer
Rollback configuration controls the order, pace, and rollback behavior of a service update. This card shows its role in “Compose, Swarm, and Portainer” and a safe diagnostic path.
Open learning card →Placement constraint — Compose, Swarm, and Portainer
Placement constraint restricts tasks to nodes with matching roles or labels. This card shows its role in “Compose, Swarm, and Portainer” and a safe diagnostic path.
Open learning card →Resource limit — Compose, Swarm, and Portainer
Resource limit limits consumption or reserves schedulable CPU and memory resources. This card shows its role in “Compose, Swarm, and Portainer” and a safe diagnostic path.
Open learning card →Resource reservation — Compose, Swarm, and Portainer
Resource reservation limits consumption or reserves schedulable CPU and memory resources. This card shows its role in “Compose, Swarm, and Portainer” and a safe diagnostic path.
Open learning card →Swarm secret — Compose, Swarm, and Portainer
Swarm secret delivers sensitive or regular configuration data to selected services in a controlled way. This card shows its role in “Compose, Swarm, and Portainer” and a safe diagnostic path.
Open learning card →Swarm config — Compose, Swarm, and Portainer
Swarm config delivers sensitive or regular configuration data to selected services in a controlled way. This card shows its role in “Compose, Swarm, and Portainer” and a safe diagnostic path.
Open learning card →Overlay network — Compose, Swarm, and Portainer
Overlay network connects services across the cluster and resolves their logical names. This card shows its role in “Compose, Swarm, and Portainer” and a safe diagnostic path.
Open learning card →Ingress network — Compose, Swarm, and Portainer
Ingress network connects services across the cluster and resolves their logical names. This card shows its role in “Compose, Swarm, and Portainer” and a safe diagnostic path.
Open learning card →Routing mesh — Compose, Swarm, and Portainer
Routing mesh connects services across the cluster and resolves their logical names. This card shows its role in “Compose, Swarm, and Portainer” and a safe diagnostic path.
Open learning card →Service discovery — Compose, Swarm, and Portainer
Service discovery connects services across the cluster and resolves their logical names. This card shows its role in “Compose, Swarm, and Portainer” and a safe diagnostic path.
Open learning card →Portainer — Compose, Swarm, and Portainer
Portainer provides a web interface for inspecting and managing Docker. This card shows its role in “Compose, Swarm, and Portainer” and a safe diagnostic path.
Open learning card →Stack editor — Compose, Swarm, and Portainer
Stack editor groups related Swarm services from a declarative stack file. This card shows its role in “Compose, Swarm, and Portainer” and a safe diagnostic path.
Open learning card →Stack deployment — Compose, Swarm, and Portainer
Stack deployment groups related Swarm services from a declarative stack file. This card shows its role in “Compose, Swarm, and Portainer” and a safe diagnostic path.
Open learning card →Service scaling — Compose, Swarm, and Portainer
Service scaling changes the desired number of identical service replicas. This card shows its role in “Compose, Swarm, and Portainer” and a safe diagnostic path.
Open learning card →Service inspect — Compose, Swarm, and Portainer
Service inspect shows the complete active service specification held by the Swarm manager. This card shows its role in “Compose, Swarm, and Portainer” and a safe diagnostic path.
Open learning card →Level 1 · Module 14Reverse proxies and routingFundamentals, operations, and troubleshooting for Reverse proxies and routing.32 terms
Reverse proxy — Reverse proxies and routing
Reverse proxy mediates connections between client and destination but in opposite trust directions. This card shows its role in “Reverse proxies and routing” and a safe diagnostic path.
Open learning card →Forward proxy — Reverse proxies and routing
Forward proxy mediates connections between client and destination but in opposite trust directions. This card shows its role in “Reverse proxies and routing” and a safe diagnostic path.
Open learning card →Router rule — Reverse proxies and routing
Router rule decides from host or path which router handles a request. This card shows its role in “Reverse proxies and routing” and a safe diagnostic path.
Open learning card →Host rule — Reverse proxies and routing
Host rule decides from host or path which router handles a request. This card shows its role in “Reverse proxies and routing” and a safe diagnostic path.
Open learning card →PathPrefix rule — Reverse proxies and routing
PathPrefix rule decides from host or path which router handles a request. This card shows its role in “Reverse proxies and routing” and a safe diagnostic path.
Open learning card →EntryPoint — Reverse proxies and routing
EntryPoint defines the listening address and port of a Traefik ingress. This card shows its role in “Reverse proxies and routing” and a safe diagnostic path.
Open learning card →Middleware — Reverse proxies and routing
Middleware modifies or checks a request between router and backend. This card shows its role in “Reverse proxies and routing” and a safe diagnostic path.
Open learning card →Backend service — Reverse proxies and routing
Backend service describes reachable target instances and their distribution behind the proxy. This card shows its role in “Reverse proxies and routing” and a safe diagnostic path.
Open learning card →Load balancer — Reverse proxies and routing
Load balancer describes reachable target instances and their distribution behind the proxy. This card shows its role in “Reverse proxies and routing” and a safe diagnostic path.
Open learning card →Upstream — Reverse proxies and routing
Upstream describes reachable target instances and their distribution behind the proxy. This card shows its role in “Reverse proxies and routing” and a safe diagnostic path.
Open learning card →Traefik — Reverse proxies and routing
Traefik is a reverse-proxy web server for routing, TLS, and forwarding. This card shows its role in “Reverse proxies and routing” and a safe diagnostic path.
Open learning card →Traefik provider — Reverse proxies and routing
Traefik provider supplies Traefik with dynamic routing objects from an infrastructure source. This card shows its role in “Reverse proxies and routing” and a safe diagnostic path.
Open learning card →Docker provider — Reverse proxies and routing
Docker provider supplies Traefik with dynamic routing objects from an infrastructure source. This card shows its role in “Reverse proxies and routing” and a safe diagnostic path.
Open learning card →Swarm provider — Reverse proxies and routing
Swarm provider supplies Traefik with dynamic routing objects from an infrastructure source. This card shows its role in “Reverse proxies and routing” and a safe diagnostic path.
Open learning card →Traefik label — Reverse proxies and routing
Traefik label encodes dynamic Traefik configuration directly on a container or service. This card shows its role in “Reverse proxies and routing” and a safe diagnostic path.
Open learning card →nginx — Reverse proxies and routing
nginx is a reverse-proxy web server for routing, TLS, and forwarding. This card shows its role in “Reverse proxies and routing” and a safe diagnostic path.
Open learning card →nginx server block — Reverse proxies and routing
nginx server block selects the virtual host, path scope, and forwarding target in nginx. This card shows its role in “Reverse proxies and routing” and a safe diagnostic path.
Open learning card →nginx location block — Reverse proxies and routing
nginx location block selects the virtual host, path scope, and forwarding target in nginx. This card shows its role in “Reverse proxies and routing” and a safe diagnostic path.
Open learning card →proxy_pass — Reverse proxies and routing
proxy_pass selects the virtual host, path scope, and forwarding target in nginx. This card shows its role in “Reverse proxies and routing” and a safe diagnostic path.
Open learning card →Forwarded header — Reverse proxies and routing
Forwarded header carries original protocol, host, or client address across proxy boundaries. This card shows its role in “Reverse proxies and routing” and a safe diagnostic path.
Open learning card →X-Forwarded-For — Reverse proxies and routing
X-Forwarded-For carries the original client IP as an ordered proxy chain. This card shows its role in “Reverse proxies and routing” and a safe diagnostic path.
Open learning card →X-Forwarded-Proto — Reverse proxies and routing
X-Forwarded-Proto tells the backend the original client scheme such as HTTPS. This card shows its role in “Reverse proxies and routing” and a safe diagnostic path.
Open learning card →X-Real-IP — Reverse proxies and routing
X-Real-IP carries original protocol, host, or client address across proxy boundaries. This card shows its role in “Reverse proxies and routing” and a safe diagnostic path.
Open learning card →WebSocket upgrade — Reverse proxies and routing
WebSocket upgrade upgrades an HTTP connection to a persistent bidirectional connection. This card shows its role in “Reverse proxies and routing” and a safe diagnostic path.
Open learning card →Request timeout — Reverse proxies and routing
Request timeout limits waiting time for connection setup or an upstream response. This card shows its role in “Reverse proxies and routing” and a safe diagnostic path.
Open learning card →Response timeout — Reverse proxies and routing
Response timeout limits waiting time for connection setup or an upstream response. This card shows its role in “Reverse proxies and routing” and a safe diagnostic path.
Open learning card →Upload limit — Reverse proxies and routing
Upload limit limits request size or frequency before the backend. This card shows its role in “Reverse proxies and routing” and a safe diagnostic path.
Open learning card →Request body limit — Reverse proxies and routing
Request body limit limits request size or frequency before the backend. This card shows its role in “Reverse proxies and routing” and a safe diagnostic path.
Open learning card →Sticky session — Reverse proxies and routing
Sticky session binds repeated client requests to the same backend instance. This card shows its role in “Reverse proxies and routing” and a safe diagnostic path.
Open learning card →Rate limit — Reverse proxies and routing
Rate limit limits request size or frequency before the backend. This card shows its role in “Reverse proxies and routing” and a safe diagnostic path.
Open learning card →Compression middleware — Reverse proxies and routing
Compression middleware compresses eligible HTTP responses according to Accept-Encoding. This card shows its role in “Reverse proxies and routing” and a safe diagnostic path.
Open learning card →Access log — Reverse proxies and routing
Access log records each proxy request with status, target, and duration. This card shows its role in “Reverse proxies and routing” and a safe diagnostic path.
Open learning card →Level 1 · Module 15Frontend fundamentalsFundamentals, operations, and troubleshooting for Frontend fundamentals.32 terms
HTML document — Frontend fundamentals
HTML document structures content and interaction as accessible browser document elements. This card shows its role in “Frontend fundamentals” and a safe diagnostic path.
Open learning card →DOM — Frontend fundamentals
DOM is the runtime-mutable object structure of the loaded HTML document. This card shows its role in “Frontend fundamentals” and a safe diagnostic path.
Open learning card →HTML element — Frontend fundamentals
HTML element structures content and interaction as accessible browser document elements. This card shows its role in “Frontend fundamentals” and a safe diagnostic path.
Open learning card →HTML attribute — Frontend fundamentals
HTML attribute structures content and interaction as accessible browser document elements. This card shows its role in “Frontend fundamentals” and a safe diagnostic path.
Open learning card →Semantic HTML — Frontend fundamentals
Semantic HTML structures content and interaction as accessible browser document elements. This card shows its role in “Frontend fundamentals” and a safe diagnostic path.
Open learning card →Form — Frontend fundamentals
Form structures content and interaction as accessible browser document elements. This card shows its role in “Frontend fundamentals” and a safe diagnostic path.
Open learning card →Input field — Frontend fundamentals
Input field structures content and interaction as accessible browser document elements. This card shows its role in “Frontend fundamentals” and a safe diagnostic path.
Open learning card →Button — Frontend fundamentals
Button structures content and interaction as accessible browser document elements. This card shows its role in “Frontend fundamentals” and a safe diagnostic path.
Open learning card →Label — Frontend fundamentals
Label structures content and interaction as accessible browser document elements. This card shows its role in “Frontend fundamentals” and a safe diagnostic path.
Open learning card →CSS — Frontend fundamentals
CSS controls selection, values, and size calculation of visual presentation. This card shows its role in “Frontend fundamentals” and a safe diagnostic path.
Open learning card →CSS selector — Frontend fundamentals
CSS selector controls selection, values, and size calculation of visual presentation. This card shows its role in “Frontend fundamentals” and a safe diagnostic path.
Open learning card →CSS class — Frontend fundamentals
CSS class controls selection, values, and size calculation of visual presentation. This card shows its role in “Frontend fundamentals” and a safe diagnostic path.
Open learning card →CSS custom property — Frontend fundamentals
CSS custom property controls selection, values, and size calculation of visual presentation. This card shows its role in “Frontend fundamentals” and a safe diagnostic path.
Open learning card →CSS box model — Frontend fundamentals
CSS box model controls selection, values, and size calculation of visual presentation. This card shows its role in “Frontend fundamentals” and a safe diagnostic path.
Open learning card →Flexbox — Frontend fundamentals
Flexbox arranges elements along one or two layout axes. This card shows its role in “Frontend fundamentals” and a safe diagnostic path.
Open learning card →CSS Grid — Frontend fundamentals
CSS Grid arranges elements along one or two layout axes. This card shows its role in “Frontend fundamentals” and a safe diagnostic path.
Open learning card →Responsive design — Frontend fundamentals
Responsive design adapts layout and interaction to available space and device characteristics. This card shows its role in “Frontend fundamentals” and a safe diagnostic path.
Open learning card →Media query — Frontend fundamentals
Media query adapts layout and interaction to available space and device characteristics. This card shows its role in “Frontend fundamentals” and a safe diagnostic path.
Open learning card →JavaScript — Frontend fundamentals
JavaScript provides the language and standard used to program browser state and interaction. This card shows its role in “Frontend fundamentals” and a safe diagnostic path.
Open learning card →ECMAScript — Frontend fundamentals
ECMAScript provides the language and standard used to program browser state and interaction. This card shows its role in “Frontend fundamentals” and a safe diagnostic path.
Open learning card →Event — Frontend fundamentals
Event reports a user or browser action and attaches reacting code. This card shows its role in “Frontend fundamentals” and a safe diagnostic path.
Open learning card →Event listener — Frontend fundamentals
Event listener reports a user or browser action and attaches reacting code. This card shows its role in “Frontend fundamentals” and a safe diagnostic path.
Open learning card →Fetch API — Frontend fundamentals
Fetch API performs asynchronous network work and represents its eventual result. This card shows its role in “Frontend fundamentals” and a safe diagnostic path.
Open learning card →Promise — Frontend fundamentals
Promise performs asynchronous network work and represents its eventual result. This card shows its role in “Frontend fundamentals” and a safe diagnostic path.
Open learning card →async and await — Frontend fundamentals
async and await performs asynchronous network work and represents its eventual result. This card shows its role in “Frontend fundamentals” and a safe diagnostic path.
Open learning card →Browser storage — Frontend fundamentals
Browser storage stores small key-value data in the browser with different lifetimes. This card shows its role in “Frontend fundamentals” and a safe diagnostic path.
Open learning card →Local Storage — Frontend fundamentals
Local Storage stores small key-value data in the browser with different lifetimes. This card shows its role in “Frontend fundamentals” and a safe diagnostic path.
Open learning card →Session Storage — Frontend fundamentals
Session Storage stores small key-value data in the browser with different lifetimes. This card shows its role in “Frontend fundamentals” and a safe diagnostic path.
Open learning card →File upload — Frontend fundamentals
File upload passes user-selected files to browser logic and an upload endpoint. This card shows its role in “Frontend fundamentals” and a safe diagnostic path.
Open learning card →Drag and drop — Frontend fundamentals
Drag and drop passes user-selected files to browser logic and an upload endpoint. This card shows its role in “Frontend fundamentals” and a safe diagnostic path.
Open learning card →Progress indicator — Frontend fundamentals
Progress indicator visualizes measurable upload or processing progress instead of mere waiting. This card shows its role in “Frontend fundamentals” and a safe diagnostic path.
Open learning card →Web accessibility — Frontend fundamentals
Web accessibility makes content usable by keyboard, screen readers, and sufficient contrast. This card shows its role in “Frontend fundamentals” and a safe diagnostic path.
Open learning card →Level 1 · Module 16Backends and web APIsFundamentals, operations, and troubleshooting for Backends and web APIs.32 terms
Backend — Backends and web APIs
Backend processes server-side rules, data access, and responses behind a web interface. This card shows its role in “Backends and web APIs” and a safe diagnostic path.
Open learning card →Application server — Backends and web APIs
Application server processes server-side rules, data access, and responses behind a web interface. This card shows its role in “Backends and web APIs” and a safe diagnostic path.
Open learning card →Node.js — Backends and web APIs
Node.js forms the JavaScript runtime, package tool, and project manifest of a Node project. This card shows its role in “Backends and web APIs” and a safe diagnostic path.
Open learning card →npm — Backends and web APIs
npm forms the JavaScript runtime, package tool, and project manifest of a Node project. This card shows its role in “Backends and web APIs” and a safe diagnostic path.
Open learning card →package.json — Backends and web APIs
package.json forms the JavaScript runtime, package tool, and project manifest of a Node project. This card shows its role in “Backends and web APIs” and a safe diagnostic path.
Open learning card →Python — Backends and web APIs
Python forms the language, isolated package environment, and installer of a Python project. This card shows its role in “Backends and web APIs” and a safe diagnostic path.
Open learning card →Virtual environment — Backends and web APIs
Virtual environment forms the language, isolated package environment, and installer of a Python project. This card shows its role in “Backends and web APIs” and a safe diagnostic path.
Open learning card →pip — Backends and web APIs
pip forms the language, isolated package environment, and installer of a Python project. This card shows its role in “Backends and web APIs” and a safe diagnostic path.
Open learning card →FastAPI — Backends and web APIs
FastAPI serves a Python web application through an ASGI server and optional process manager. This card shows its role in “Backends and web APIs” and a safe diagnostic path.
Open learning card →ASGI — Backends and web APIs
ASGI serves a Python web application through an ASGI server and optional process manager. This card shows its role in “Backends and web APIs” and a safe diagnostic path.
Open learning card →Uvicorn — Backends and web APIs
Uvicorn serves a Python web application through an ASGI server and optional process manager. This card shows its role in “Backends and web APIs” and a safe diagnostic path.
Open learning card →Endpoint — Backends and web APIs
Endpoint maps an HTTP method and URL path to a backend function. This card shows its role in “Backends and web APIs” and a safe diagnostic path.
Open learning card →Route — Backends and web APIs
Route maps an HTTP method and URL path to a backend function. This card shows its role in “Backends and web APIs” and a safe diagnostic path.
Open learning card →Request model — Backends and web APIs
Request model defines and validates the shape, types, and output of API data. This card shows its role in “Backends and web APIs” and a safe diagnostic path.
Open learning card →Response model — Backends and web APIs
Response model defines and validates the shape, types, and output of API data. This card shows its role in “Backends and web APIs” and a safe diagnostic path.
Open learning card →Validation — Backends and web APIs
Validation defines and validates the shape, types, and output of API data. This card shows its role in “Backends and web APIs” and a safe diagnostic path.
Open learning card →Middleware — Backends and web APIs
Middleware runs reusable cross-cutting logic or supplied dependencies per request. This card shows its role in “Backends and web APIs” and a safe diagnostic path.
Open learning card →Dependency injection — Backends and web APIs
Dependency injection runs reusable cross-cutting logic or supplied dependencies per request. This card shows its role in “Backends and web APIs” and a safe diagnostic path.
Open learning card →Background task — Backends and web APIs
Background task moves work out of the direct response path or executes waiting work concurrently. This card shows its role in “Backends and web APIs” and a safe diagnostic path.
Open learning card →Multipart upload — Backends and web APIs
Multipart upload transfers large files in chunks rather than as one JSON object. This card shows its role in “Backends and web APIs” and a safe diagnostic path.
Open learning card →Streaming response — Backends and web APIs
Streaming response transfers large files in chunks rather than as one JSON object. This card shows its role in “Backends and web APIs” and a safe diagnostic path.
Open learning card →Server-sent events — Backends and web APIs
Server-sent events keeps a connection open for server updates or bidirectional messages. This card shows its role in “Backends and web APIs” and a safe diagnostic path.
Open learning card →WebSocket — Backends and web APIs
WebSocket keeps a connection open for server updates or bidirectional messages. This card shows its role in “Backends and web APIs” and a safe diagnostic path.
Open learning card →OpenAPI — Backends and web APIs
OpenAPI describes API contracts in machine-readable form and presents them interactively. This card shows its role in “Backends and web APIs” and a safe diagnostic path.
Open learning card →Swagger UI — Backends and web APIs
Swagger UI describes API contracts in machine-readable form and presents them interactively. This card shows its role in “Backends and web APIs” and a safe diagnostic path.
Open learning card →Error handling — Backends and web APIs
Error handling translates internal failures into controlled, logged HTTP responses. This card shows its role in “Backends and web APIs” and a safe diagnostic path.
Open learning card →Exception handler — Backends and web APIs
Exception handler translates internal failures into controlled, logged HTTP responses. This card shows its role in “Backends and web APIs” and a safe diagnostic path.
Open learning card →CORS — Backends and web APIs
CORS defines which browser origins may read an API or send credentials. This card shows its role in “Backends and web APIs” and a safe diagnostic path.
Open learning card →Pydantic — Backends and web APIs
Pydantic defines and validates the shape, types, and output of API data. This card shows its role in “Backends and web APIs” and a safe diagnostic path.
Open learning card →Async function — Backends and web APIs
Async function moves work out of the direct response path or executes waiting work concurrently. This card shows its role in “Backends and web APIs” and a safe diagnostic path.
Open learning card →Worker process — Backends and web APIs
Worker process moves work out of the direct response path or executes waiting work concurrently. This card shows its role in “Backends and web APIs” and a safe diagnostic path.
Open learning card →Gunicorn — Backends and web APIs
Gunicorn serves a Python web application through an ASGI server and optional process manager. This card shows its role in “Backends and web APIs” and a safe diagnostic path.
Open learning card →Level 2 · Module 17PostgreSQLFundamentals, operations, and troubleshooting for PostgreSQL.32 terms
Relational database — PostgreSQL
Relational database stores structured data transactionally and serves it to multiple clients through SQL. This card shows its role in “PostgreSQL” and a safe diagnostic path.
Open learning card →PostgreSQL — PostgreSQL
PostgreSQL stores structured data transactionally and serves it to multiple clients through SQL. This card shows its role in “PostgreSQL” and a safe diagnostic path.
Open learning card →Database server — PostgreSQL
Database server stores structured data transactionally and serves it to multiple clients through SQL. This card shows its role in “PostgreSQL” and a safe diagnostic path.
Open learning card →Database — PostgreSQL
Database stores structured data transactionally and serves it to multiple clients through SQL. This card shows its role in “PostgreSQL” and a safe diagnostic path.
Open learning card →Database schema — PostgreSQL
Database schema organizes records into named structures with defined types. This card shows its role in “PostgreSQL” and a safe diagnostic path.
Open learning card →Table — PostgreSQL
Table organizes records into named structures with defined types. This card shows its role in “PostgreSQL” and a safe diagnostic path.
Open learning card →Column — PostgreSQL
Column organizes records into named structures with defined types. This card shows its role in “PostgreSQL” and a safe diagnostic path.
Open learning card →Row — PostgreSQL
Row organizes records into named structures with defined types. This card shows its role in “PostgreSQL” and a safe diagnostic path.
Open learning card →Data type — PostgreSQL
Data type organizes records into named structures with defined types. This card shows its role in “PostgreSQL” and a safe diagnostic path.
Open learning card →Primary key — PostgreSQL
Primary key enforces identity, relationships, or valid values directly in the database. This card shows its role in “PostgreSQL” and a safe diagnostic path.
Open learning card →Foreign key — PostgreSQL
Foreign key enforces identity, relationships, or valid values directly in the database. This card shows its role in “PostgreSQL” and a safe diagnostic path.
Open learning card →Unique constraint — PostgreSQL
Unique constraint enforces identity, relationships, or valid values directly in the database. This card shows its role in “PostgreSQL” and a safe diagnostic path.
Open learning card →Not-null constraint — PostgreSQL
Not-null constraint enforces identity, relationships, or valid values directly in the database. This card shows its role in “PostgreSQL” and a safe diagnostic path.
Open learning card →Database index — PostgreSQL
Database index accelerates matching search and sort operations at the cost of storage and writes. This card shows its role in “PostgreSQL” and a safe diagnostic path.
Open learning card →B-tree index — PostgreSQL
B-tree index accelerates matching search and sort operations at the cost of storage and writes. This card shows its role in “PostgreSQL” and a safe diagnostic path.
Open learning card →SQL — PostgreSQL
SQL is a statement for reading, writing, or joining relational data. This card shows its role in “PostgreSQL” and a safe diagnostic path.
Open learning card →SELECT — PostgreSQL
SELECT is a statement for reading, writing, or joining relational data. This card shows its role in “PostgreSQL” and a safe diagnostic path.
Open learning card →INSERT — PostgreSQL
INSERT is a statement for reading, writing, or joining relational data. This card shows its role in “PostgreSQL” and a safe diagnostic path.
Open learning card →UPDATE — PostgreSQL
UPDATE is a statement for reading, writing, or joining relational data. This card shows its role in “PostgreSQL” and a safe diagnostic path.
Open learning card →DELETE — PostgreSQL
DELETE is a statement for reading, writing, or joining relational data. This card shows its role in “PostgreSQL” and a safe diagnostic path.
Open learning card →JOIN — PostgreSQL
JOIN is a statement for reading, writing, or joining relational data. This card shows its role in “PostgreSQL” and a safe diagnostic path.
Open learning card →Transaction — PostgreSQL
Transaction groups changes so they fully apply or are safely discarded. This card shows its role in “PostgreSQL” and a safe diagnostic path.
Open learning card →COMMIT — PostgreSQL
COMMIT groups changes so they fully apply or are safely discarded. This card shows its role in “PostgreSQL” and a safe diagnostic path.
Open learning card →ROLLBACK — PostgreSQL
ROLLBACK groups changes so they fully apply or are safely discarded. This card shows its role in “PostgreSQL” and a safe diagnostic path.
Open learning card →ACID — PostgreSQL
ACID groups changes so they fully apply or are safely discarded. This card shows its role in “PostgreSQL” and a safe diagnostic path.
Open learning card →Connection pool — PostgreSQL
Connection pool keeps a limited set of reusable database connections. This card shows its role in “PostgreSQL” and a safe diagnostic path.
Open learning card →Database migration — PostgreSQL
Database migration moves schema and data reproducibly from one version to the next. This card shows its role in “PostgreSQL” and a safe diagnostic path.
Open learning card →Database role — PostgreSQL
Database role defines database identity and allowed operations according to least privilege. This card shows its role in “PostgreSQL” and a safe diagnostic path.
Open learning card →Database user — PostgreSQL
Database user defines database identity and allowed operations according to least privilege. This card shows its role in “PostgreSQL” and a safe diagnostic path.
Open learning card →Database permission — PostgreSQL
Database permission defines database identity and allowed operations according to least privilege. This card shows its role in “PostgreSQL” and a safe diagnostic path.
Open learning card →pg_dump — PostgreSQL
pg_dump exports logical PostgreSQL structures and data into a backup format. This card shows its role in “PostgreSQL” and a safe diagnostic path.
Open learning card →pg_restore — PostgreSQL
pg_restore restores an archive created by pg_dump in a controlled way. This card shows its role in “PostgreSQL” and a safe diagnostic path.
Open learning card →Level 2 · Module 18SQLite, Redis, and queuesFundamentals, operations, and troubleshooting for SQLite, Redis, and queues.32 terms
SQLite — SQLite, Redis, and queues
SQLite stores a relational database directly in one local file. This card shows its role in “SQLite, Redis, and queues” and a safe diagnostic path.
Open learning card →Database file — SQLite, Redis, and queues
Database file stores a relational database directly in one local file. This card shows its role in “SQLite, Redis, and queues” and a safe diagnostic path.
Open learning card →Write-ahead logging — SQLite, Redis, and queues
Write-ahead logging writes changes to a WAL log first and improves concurrent reads. This card shows its role in “SQLite, Redis, and queues” and a safe diagnostic path.
Open learning card →SQLite transaction — SQLite, Redis, and queues
SQLite transaction stores a relational database directly in one local file. This card shows its role in “SQLite, Redis, and queues” and a safe diagnostic path.
Open learning card →Redis — SQLite, Redis, and queues
Redis keeps data primarily in memory for very fast key access. This card shows its role in “SQLite, Redis, and queues” and a safe diagnostic path.
Open learning card →In-memory database — SQLite, Redis, and queues
In-memory database keeps data primarily in memory for very fast key access. This card shows its role in “SQLite, Redis, and queues” and a safe diagnostic path.
Open learning card →Redis key — SQLite, Redis, and queues
Redis key is a Redis data structure with its own access and ordering semantics. This card shows its role in “SQLite, Redis, and queues” and a safe diagnostic path.
Open learning card →Redis value — SQLite, Redis, and queues
Redis value is a Redis data structure with its own access and ordering semantics. This card shows its role in “SQLite, Redis, and queues” and a safe diagnostic path.
Open learning card →Expiration — SQLite, Redis, and queues
Expiration automatically deletes a Redis key after a defined remaining lifetime. This card shows its role in “SQLite, Redis, and queues” and a safe diagnostic path.
Open learning card →Redis TTL — SQLite, Redis, and queues
Redis TTL automatically deletes a Redis key after a defined remaining lifetime. This card shows its role in “SQLite, Redis, and queues” and a safe diagnostic path.
Open learning card →Redis hash — SQLite, Redis, and queues
Redis hash is a Redis data structure with its own access and ordering semantics. This card shows its role in “SQLite, Redis, and queues” and a safe diagnostic path.
Open learning card →Redis list — SQLite, Redis, and queues
Redis list is a Redis data structure with its own access and ordering semantics. This card shows its role in “SQLite, Redis, and queues” and a safe diagnostic path.
Open learning card →Redis set — SQLite, Redis, and queues
Redis set is a Redis data structure with its own access and ordering semantics. This card shows its role in “SQLite, Redis, and queues” and a safe diagnostic path.
Open learning card →Redis sorted set — SQLite, Redis, and queues
Redis sorted set is a Redis data structure with its own access and ordering semantics. This card shows its role in “SQLite, Redis, and queues” and a safe diagnostic path.
Open learning card →Redis Pub/Sub — SQLite, Redis, and queues
Redis Pub/Sub distributes transient messages to currently connected subscribers without persistence. This card shows its role in “SQLite, Redis, and queues” and a safe diagnostic path.
Open learning card →Redis persistence — SQLite, Redis, and queues
Redis persistence persists Redis data periodically or as an append-only change log. This card shows its role in “SQLite, Redis, and queues” and a safe diagnostic path.
Open learning card →RDB snapshot — SQLite, Redis, and queues
RDB snapshot persists Redis data periodically or as an append-only change log. This card shows its role in “SQLite, Redis, and queues” and a safe diagnostic path.
Open learning card →AOF — SQLite, Redis, and queues
AOF persists Redis data periodically or as an append-only change log. This card shows its role in “SQLite, Redis, and queues” and a safe diagnostic path.
Open learning card →Cache — SQLite, Redis, and queues
Cache avoids expensive recomputation through reusable results and measurable hits. This card shows its role in “SQLite, Redis, and queues” and a safe diagnostic path.
Open learning card →Cache miss — SQLite, Redis, and queues
Cache miss avoids expensive recomputation through reusable results and measurable hits. This card shows its role in “SQLite, Redis, and queues” and a safe diagnostic path.
Open learning card →Cache hit — SQLite, Redis, and queues
Cache hit avoids expensive recomputation through reusable results and measurable hits. This card shows its role in “SQLite, Redis, and queues” and a safe diagnostic path.
Open learning card →Job queue — SQLite, Redis, and queues
Job queue moves discrete work items from a producer to a processing worker. This card shows its role in “SQLite, Redis, and queues” and a safe diagnostic path.
Open learning card →Job — SQLite, Redis, and queues
Job moves discrete work items from a producer to a processing worker. This card shows its role in “SQLite, Redis, and queues” and a safe diagnostic path.
Open learning card →Producer — SQLite, Redis, and queues
Producer moves discrete work items from a producer to a processing worker. This card shows its role in “SQLite, Redis, and queues” and a safe diagnostic path.
Open learning card →Consumer — SQLite, Redis, and queues
Consumer moves discrete work items from a producer to a processing worker. This card shows its role in “SQLite, Redis, and queues” and a safe diagnostic path.
Open learning card →Queue worker — SQLite, Redis, and queues
Queue worker moves discrete work items from a producer to a processing worker. This card shows its role in “SQLite, Redis, and queues” and a safe diagnostic path.
Open learning card →FIFO — SQLite, Redis, and queues
FIFO moves discrete work items from a producer to a processing worker. This card shows its role in “SQLite, Redis, and queues” and a safe diagnostic path.
Open learning card →Retry — SQLite, Redis, and queues
Retry reprocesses failed jobs or isolates them after limited attempts. This card shows its role in “SQLite, Redis, and queues” and a safe diagnostic path.
Open learning card →Dead-letter queue — SQLite, Redis, and queues
Dead-letter queue reprocesses failed jobs or isolates them after limited attempts. This card shows its role in “SQLite, Redis, and queues” and a safe diagnostic path.
Open learning card →Visibility timeout — SQLite, Redis, and queues
Visibility timeout temporarily reserves a fetched job until it is acknowledged or becomes visible again. This card shows its role in “SQLite, Redis, and queues” and a safe diagnostic path.
Open learning card →Idempotency key — SQLite, Redis, and queues
Idempotency key makes repeated equivalent requests have the same effect through a stable key. This card shows its role in “SQLite, Redis, and queues” and a safe diagnostic path.
Open learning card →Distributed lock — SQLite, Redis, and queues
Distributed lock coordinates exclusive access by multiple processes through a shared lock key. This card shows its role in “SQLite, Redis, and queues” and a safe diagnostic path.
Open learning card →Level 2 · Module 19Accounts, authentication, and sessionsFundamentals, operations, and troubleshooting for Accounts, authentication, and sessions.32 terms
Identity — Accounts, authentication, and sessions
Identity represents a person or service identity with associated account state. This card shows its role in “Accounts, authentication, and sessions” and a safe diagnostic path.
Open learning card →Account — Accounts, authentication, and sessions
Account represents a person or service identity with associated account state. This card shows its role in “Accounts, authentication, and sessions” and a safe diagnostic path.
Open learning card →Registration — Accounts, authentication, and sessions
Registration represents a person or service identity with associated account state. This card shows its role in “Accounts, authentication, and sessions” and a safe diagnostic path.
Open learning card →Login — Accounts, authentication, and sessions
Login verifies credentials and starts or ends an authenticated context. This card shows its role in “Accounts, authentication, and sessions” and a safe diagnostic path.
Open learning card →Logout — Accounts, authentication, and sessions
Logout verifies credentials and starts or ends an authenticated context. This card shows its role in “Accounts, authentication, and sessions” and a safe diagnostic path.
Open learning card →Authentication — Accounts, authentication, and sessions
Authentication verifies credentials and starts or ends an authenticated context. This card shows its role in “Accounts, authentication, and sessions” and a safe diagnostic path.
Open learning card →Authorization — Accounts, authentication, and sessions
Authorization decides after identity verification whether a specific action is allowed. This card shows its role in “Accounts, authentication, and sessions” and a safe diagnostic path.
Open learning card →Password hash — Accounts, authentication, and sessions
Password hash stores passwords as deliberately expensive one-way derivations with an individual random value. This card shows its role in “Accounts, authentication, and sessions” and a safe diagnostic path.
Open learning card →Salt — Accounts, authentication, and sessions
Salt stores passwords as deliberately expensive one-way derivations with an individual random value. This card shows its role in “Accounts, authentication, and sessions” and a safe diagnostic path.
Open learning card →Argon2 — Accounts, authentication, and sessions
Argon2 stores passwords as deliberately expensive one-way derivations with an individual random value. This card shows its role in “Accounts, authentication, and sessions” and a safe diagnostic path.
Open learning card →bcrypt — Accounts, authentication, and sessions
bcrypt stores passwords as deliberately expensive one-way derivations with an individual random value. This card shows its role in “Accounts, authentication, and sessions” and a safe diagnostic path.
Open learning card →Session — Accounts, authentication, and sessions
Session links a random browser identifier to server-side login state. This card shows its role in “Accounts, authentication, and sessions” and a safe diagnostic path.
Open learning card →Session ID — Accounts, authentication, and sessions
Session ID links a random browser identifier to server-side login state. This card shows its role in “Accounts, authentication, and sessions” and a safe diagnostic path.
Open learning card →Session cookie — Accounts, authentication, and sessions
Session cookie links a random browser identifier to server-side login state. This card shows its role in “Accounts, authentication, and sessions” and a safe diagnostic path.
Open learning card →Access token — Accounts, authentication, and sessions
Access token carries time-limited access claims or renews them without a password. This card shows its role in “Accounts, authentication, and sessions” and a safe diagnostic path.
Open learning card →Refresh token — Accounts, authentication, and sessions
Refresh token carries time-limited access claims or renews them without a password. This card shows its role in “Accounts, authentication, and sessions” and a safe diagnostic path.
Open learning card →JWT — Accounts, authentication, and sessions
JWT carries time-limited access claims or renews them without a password. This card shows its role in “Accounts, authentication, and sessions” and a safe diagnostic path.
Open learning card →OAuth 2.0 — Accounts, authentication, and sessions
OAuth 2.0 standardizes delegated authorization and adds verifiable user identity. This card shows its role in “Accounts, authentication, and sessions” and a safe diagnostic path.
Open learning card →OpenID Connect — Accounts, authentication, and sessions
OpenID Connect standardizes delegated authorization and adds verifiable user identity. This card shows its role in “Accounts, authentication, and sessions” and a safe diagnostic path.
Open learning card →Google login — Accounts, authentication, and sessions
Google login connects an external identity provider through an exactly registered callback address. This card shows its role in “Accounts, authentication, and sessions” and a safe diagnostic path.
Open learning card →Discord login — Accounts, authentication, and sessions
Discord login connects an external identity provider through an exactly registered callback address. This card shows its role in “Accounts, authentication, and sessions” and a safe diagnostic path.
Open learning card →Callback URL — Accounts, authentication, and sessions
Callback URL connects an external identity provider through an exactly registered callback address. This card shows its role in “Accounts, authentication, and sessions” and a safe diagnostic path.
Open learning card →CSRF — Accounts, authentication, and sessions
CSRF prevents or limits cross-site state-changing requests carrying existing cookies. This card shows its role in “Accounts, authentication, and sessions” and a safe diagnostic path.
Open learning card →SameSite cookie — Accounts, authentication, and sessions
SameSite cookie prevents or limits cross-site state-changing requests carrying existing cookies. This card shows its role in “Accounts, authentication, and sessions” and a safe diagnostic path.
Open learning card →Secure cookie — Accounts, authentication, and sessions
Secure cookie restricts session cookies to HTTPS and removes JavaScript access. This card shows its role in “Accounts, authentication, and sessions” and a safe diagnostic path.
Open learning card →HttpOnly cookie — Accounts, authentication, and sessions
HttpOnly cookie restricts session cookies to HTTPS and removes JavaScript access. This card shows its role in “Accounts, authentication, and sessions” and a safe diagnostic path.
Open learning card →Role model — Accounts, authentication, and sessions
Role model decides after identity verification whether a specific action is allowed. This card shows its role in “Accounts, authentication, and sessions” and a safe diagnostic path.
Open learning card →Permission check — Accounts, authentication, and sessions
Permission check decides after identity verification whether a specific action is allowed. This card shows its role in “Accounts, authentication, and sessions” and a safe diagnostic path.
Open learning card →Account recovery — Accounts, authentication, and sessions
Account recovery represents a person or service identity with associated account state. This card shows its role in “Accounts, authentication, and sessions” and a safe diagnostic path.
Open learning card →Email verification — Accounts, authentication, and sessions
Email verification confirms control of a communication channel through short-lived one-time tokens. This card shows its role in “Accounts, authentication, and sessions” and a safe diagnostic path.
Open learning card →Brute-force protection — Accounts, authentication, and sessions
Brute-force protection limits repeated login attempts per identity and source. This card shows its role in “Accounts, authentication, and sessions” and a safe diagnostic path.
Open learning card →Login rate limit — Accounts, authentication, and sessions
Login rate limit verifies credentials and starts or ends an authenticated context. This card shows its role in “Accounts, authentication, and sessions” and a safe diagnostic path.
Open learning card →Level 2 · Module 20Monitoring and observabilityFundamentals, operations, and troubleshooting for Monitoring and observability.32 terms
Monitoring — Monitoring and observability
Monitoring makes system state visible through selected signals and explorable relationships. This card shows its role in “Monitoring and observability” and a safe diagnostic path.
Open learning card →Observability — Monitoring and observability
Observability makes system state visible through selected signals and explorable relationships. This card shows its role in “Monitoring and observability” and a safe diagnostic path.
Open learning card →Metric — Monitoring and observability
Metric is a numeric time-series value with a name, labels, and timestamp. This card shows its role in “Monitoring and observability” and a safe diagnostic path.
Open learning card →Log — Monitoring and observability
Log records discrete events and bounds their local storage use. This card shows its role in “Monitoring and observability” and a safe diagnostic path.
Open learning card →Trace — Monitoring and observability
Trace links work steps or logs from the same request across service boundaries. This card shows its role in “Monitoring and observability” and a safe diagnostic path.
Open learning card →Event — Monitoring and observability
Event describes one state-changing occurrence with time and context. This card shows its role in “Monitoring and observability” and a safe diagnostic path.
Open learning card →Dashboard — Monitoring and observability
Dashboard combines selected measurements for a specific operational purpose. This card shows its role in “Monitoring and observability” and a safe diagnostic path.
Open learning card →Alert — Monitoring and observability
Alert triggers a notification for an actionable measured condition. This card shows its role in “Monitoring and observability” and a safe diagnostic path.
Open learning card →Threshold — Monitoring and observability
Threshold triggers a notification for an actionable measured condition. This card shows its role in “Monitoring and observability” and a safe diagnostic path.
Open learning card →Uptime — Monitoring and observability
Uptime measures reachability over time or through repeated external functional checks. This card shows its role in “Monitoring and observability” and a safe diagnostic path.
Open learning card →Availability check — Monitoring and observability
Availability check measures reachability over time or through repeated external functional checks. This card shows its role in “Monitoring and observability” and a safe diagnostic path.
Open learning card →Liveness probe — Monitoring and observability
Liveness probe separates process liveness from readiness to receive real traffic. This card shows its role in “Monitoring and observability” and a safe diagnostic path.
Open learning card →Readiness probe — Monitoring and observability
Readiness probe separates process liveness from readiness to receive real traffic. This card shows its role in “Monitoring and observability” and a safe diagnostic path.
Open learning card →CPU metric — Monitoring and observability
CPU metric measures utilization or saturation of a specific technical resource. This card shows its role in “Monitoring and observability” and a safe diagnostic path.
Open learning card →Memory metric — Monitoring and observability
Memory metric measures utilization or saturation of a specific technical resource. This card shows its role in “Monitoring and observability” and a safe diagnostic path.
Open learning card →Disk metric — Monitoring and observability
Disk metric measures utilization or saturation of a specific technical resource. This card shows its role in “Monitoring and observability” and a safe diagnostic path.
Open learning card →Network metric — Monitoring and observability
Network metric measures utilization or saturation of a specific technical resource. This card shows its role in “Monitoring and observability” and a safe diagnostic path.
Open learning card →GPU metric — Monitoring and observability
GPU metric measures utilization or saturation of a specific technical resource. This card shows its role in “Monitoring and observability” and a safe diagnostic path.
Open learning card →Queue metric — Monitoring and observability
Queue metric measures utilization or saturation of a specific technical resource. This card shows its role in “Monitoring and observability” and a safe diagnostic path.
Open learning card →Request rate — Monitoring and observability
Request rate quantifies request volume, error fraction, or request duration. This card shows its role in “Monitoring and observability” and a safe diagnostic path.
Open learning card →Error rate — Monitoring and observability
Error rate quantifies request volume, error fraction, or request duration. This card shows its role in “Monitoring and observability” and a safe diagnostic path.
Open learning card →Response time — Monitoring and observability
Response time quantifies request volume, error fraction, or request duration. This card shows its role in “Monitoring and observability” and a safe diagnostic path.
Open learning card →Percentile — Monitoring and observability
Percentile describes a distribution boundary instead of an outlier-sensitive average. This card shows its role in “Monitoring and observability” and a safe diagnostic path.
Open learning card →P50 — Monitoring and observability
P50 describes a distribution boundary instead of an outlier-sensitive average. This card shows its role in “Monitoring and observability” and a safe diagnostic path.
Open learning card →P95 — Monitoring and observability
P95 describes a distribution boundary instead of an outlier-sensitive average. This card shows its role in “Monitoring and observability” and a safe diagnostic path.
Open learning card →P99 — Monitoring and observability
P99 describes a distribution boundary instead of an outlier-sensitive average. This card shows its role in “Monitoring and observability” and a safe diagnostic path.
Open learning card →Prometheus — Monitoring and observability
Prometheus collects numeric metrics from instrumented targets using a pull model. This card shows its role in “Monitoring and observability” and a safe diagnostic path.
Open learning card →Exporter — Monitoring and observability
Exporter collects numeric metrics from instrumented targets using a pull model. This card shows its role in “Monitoring and observability” and a safe diagnostic path.
Open learning card →Grafana — Monitoring and observability
Grafana visualizes and alerts on data from connected observability sources. This card shows its role in “Monitoring and observability” and a safe diagnostic path.
Open learning card →Structured log — Monitoring and observability
Structured log records discrete events and bounds their local storage use. This card shows its role in “Monitoring and observability” and a safe diagnostic path.
Open learning card →Correlation ID — Monitoring and observability
Correlation ID links work steps or logs from the same request across service boundaries. This card shows its role in “Monitoring and observability” and a safe diagnostic path.
Open learning card →Log rotation — Monitoring and observability
Log rotation records discrete events and bounds their local storage use. This card shows its role in “Monitoring and observability” and a safe diagnostic path.
Open learning card →Level 2 · Module 21FFmpeg, containers, and codecsFundamentals, operations, and troubleshooting for FFmpeg, containers, and codecs.32 terms
FFmpeg — FFmpeg, containers, and codecs
FFmpeg is a command-line framework for reading, filtering, and writing media streams. This card shows its role in “FFmpeg, containers, and codecs” and a safe diagnostic path.
Open learning card →ffprobe — FFmpeg, containers, and codecs
ffprobe reads container, stream, codec, and timing information without transcoding. This card shows its role in “FFmpeg, containers, and codecs” and a safe diagnostic path.
Open learning card →Media container — FFmpeg, containers, and codecs
Media container packages encoded streams or changes only their wrapper without re-encoding. This card shows its role in “FFmpeg, containers, and codecs” and a safe diagnostic path.
Open learning card →Codec — FFmpeg, containers, and codecs
Codec defines compression and conversion between raw and encoded media. This card shows its role in “FFmpeg, containers, and codecs” and a safe diagnostic path.
Open learning card →Encoder — FFmpeg, containers, and codecs
Encoder defines compression and conversion between raw and encoded media. This card shows its role in “FFmpeg, containers, and codecs” and a safe diagnostic path.
Open learning card →Decoder — FFmpeg, containers, and codecs
Decoder defines compression and conversion between raw and encoded media. This card shows its role in “FFmpeg, containers, and codecs” and a safe diagnostic path.
Open learning card →Transcoding — FFmpeg, containers, and codecs
Transcoding defines compression and conversion between raw and encoded media. This card shows its role in “FFmpeg, containers, and codecs” and a safe diagnostic path.
Open learning card →Remuxing — FFmpeg, containers, and codecs
Remuxing packages encoded streams or changes only their wrapper without re-encoding. This card shows its role in “FFmpeg, containers, and codecs” and a safe diagnostic path.
Open learning card →Bitrate — FFmpeg, containers, and codecs
Bitrate controls data volume and quality distribution across a medium's duration. This card shows its role in “FFmpeg, containers, and codecs” and a safe diagnostic path.
Open learning card →Constant bitrate — FFmpeg, containers, and codecs
Constant bitrate controls data volume and quality distribution across a medium's duration. This card shows its role in “FFmpeg, containers, and codecs” and a safe diagnostic path.
Open learning card →Variable bitrate — FFmpeg, containers, and codecs
Variable bitrate controls data volume and quality distribution across a medium's duration. This card shows its role in “FFmpeg, containers, and codecs” and a safe diagnostic path.
Open learning card →CRF — FFmpeg, containers, and codecs
CRF controls data volume and quality distribution across a medium's duration. This card shows its role in “FFmpeg, containers, and codecs” and a safe diagnostic path.
Open learning card →Two-pass encoding — FFmpeg, containers, and codecs
Two-pass encoding controls data volume and quality distribution across a medium's duration. This card shows its role in “FFmpeg, containers, and codecs” and a safe diagnostic path.
Open learning card →Resolution — FFmpeg, containers, and codecs
Resolution determines the spatial or temporal structure of a video stream. This card shows its role in “FFmpeg, containers, and codecs” and a safe diagnostic path.
Open learning card →Aspect ratio — FFmpeg, containers, and codecs
Aspect ratio determines the spatial or temporal structure of a video stream. This card shows its role in “FFmpeg, containers, and codecs” and a safe diagnostic path.
Open learning card →Frame rate — FFmpeg, containers, and codecs
Frame rate determines the spatial or temporal structure of a video stream. This card shows its role in “FFmpeg, containers, and codecs” and a safe diagnostic path.
Open learning card →Keyframe — FFmpeg, containers, and codecs
Keyframe determines the spatial or temporal structure of a video stream. This card shows its role in “FFmpeg, containers, and codecs” and a safe diagnostic path.
Open learning card →GOP — FFmpeg, containers, and codecs
GOP determines the spatial or temporal structure of a video stream. This card shows its role in “FFmpeg, containers, and codecs” and a safe diagnostic path.
Open learning card →Pixel format — FFmpeg, containers, and codecs
Pixel format describes digital color channels, range, and color resolution of an image. This card shows its role in “FFmpeg, containers, and codecs” and a safe diagnostic path.
Open learning card →Color space — FFmpeg, containers, and codecs
Color space describes digital color channels, range, and color resolution of an image. This card shows its role in “FFmpeg, containers, and codecs” and a safe diagnostic path.
Open learning card →Chroma subsampling — FFmpeg, containers, and codecs
Chroma subsampling describes digital color channels, range, and color resolution of an image. This card shows its role in “FFmpeg, containers, and codecs” and a safe diagnostic path.
Open learning card →H.264 — FFmpeg, containers, and codecs
H.264 is a video codec with its own balance of quality, compute cost, and compatibility. This card shows its role in “FFmpeg, containers, and codecs” and a safe diagnostic path.
Open learning card →H.265 — FFmpeg, containers, and codecs
H.265 is a video codec with its own balance of quality, compute cost, and compatibility. This card shows its role in “FFmpeg, containers, and codecs” and a safe diagnostic path.
Open learning card →VP9 — FFmpeg, containers, and codecs
VP9 is a video codec with its own balance of quality, compute cost, and compatibility. This card shows its role in “FFmpeg, containers, and codecs” and a safe diagnostic path.
Open learning card →AV1 — FFmpeg, containers, and codecs
AV1 is a video codec with its own balance of quality, compute cost, and compatibility. This card shows its role in “FFmpeg, containers, and codecs” and a safe diagnostic path.
Open learning card →AAC — FFmpeg, containers, and codecs
AAC is a lossy audio codec with different container and device profiles. This card shows its role in “FFmpeg, containers, and codecs” and a safe diagnostic path.
Open learning card →Opus — FFmpeg, containers, and codecs
Opus is a lossy audio codec with different container and device profiles. This card shows its role in “FFmpeg, containers, and codecs” and a safe diagnostic path.
Open learning card →MP3 — FFmpeg, containers, and codecs
MP3 is a lossy audio codec with different container and device profiles. This card shows its role in “FFmpeg, containers, and codecs” and a safe diagnostic path.
Open learning card →Stream mapping — FFmpeg, containers, and codecs
Stream mapping explicitly selects which video, audio, or subtitle streams are written. This card shows its role in “FFmpeg, containers, and codecs” and a safe diagnostic path.
Open learning card →Filtergraph — FFmpeg, containers, and codecs
Filtergraph connects media filters with named inputs and outputs into a processing pipeline. This card shows its role in “FFmpeg, containers, and codecs” and a safe diagnostic path.
Open learning card →Hardware encoding — FFmpeg, containers, and codecs
Hardware encoding performs video encoding on specialized hardware or general CPU cores. This card shows its role in “FFmpeg, containers, and codecs” and a safe diagnostic path.
Open learning card →Software encoding — FFmpeg, containers, and codecs
Software encoding performs video encoding on specialized hardware or general CPU cores. This card shows its role in “FFmpeg, containers, and codecs” and a safe diagnostic path.
Open learning card →Level 2 · Module 22Media, image, and document formatsFundamentals, operations, and troubleshooting for Media, image, and document formats.32 terms
MP4 — Media, image, and document formats
MP4 is a media container that bundles supported video, audio, and metadata streams. This card shows its role in “Media, image, and document formats” and a safe diagnostic path.
Open learning card →WebM — Media, image, and document formats
WebM is a media container that bundles supported video, audio, and metadata streams. This card shows its role in “Media, image, and document formats” and a safe diagnostic path.
Open learning card →Matroska — Media, image, and document formats
Matroska is a media container that bundles supported video, audio, and metadata streams. This card shows its role in “Media, image, and document formats” and a safe diagnostic path.
Open learning card →MOV — Media, image, and document formats
MOV is a media container that bundles supported video, audio, and metadata streams. This card shows its role in “Media, image, and document formats” and a safe diagnostic path.
Open learning card →AVI — Media, image, and document formats
AVI is a media container that bundles supported video, audio, and metadata streams. This card shows its role in “Media, image, and document formats” and a safe diagnostic path.
Open learning card →WAV — Media, image, and document formats
WAV stores audio uncompressed or losslessly and suits editing and archiving. This card shows its role in “Media, image, and document formats” and a safe diagnostic path.
Open learning card →FLAC — Media, image, and document formats
FLAC stores audio uncompressed or losslessly and suits editing and archiving. This card shows its role in “Media, image, and document formats” and a safe diagnostic path.
Open learning card →OGG — Media, image, and document formats
OGG is a media container that bundles supported video, audio, and metadata streams. This card shows its role in “Media, image, and document formats” and a safe diagnostic path.
Open learning card →M4A — Media, image, and document formats
M4A is a media container that bundles supported video, audio, and metadata streams. This card shows its role in “Media, image, and document formats” and a safe diagnostic path.
Open learning card →PNG — Media, image, and document formats
PNG is a raster image format with its own support for quality, animation, or transparency. This card shows its role in “Media, image, and document formats” and a safe diagnostic path.
Open learning card →JPEG — Media, image, and document formats
JPEG is a raster image format with its own support for quality, animation, or transparency. This card shows its role in “Media, image, and document formats” and a safe diagnostic path.
Open learning card →WebP — Media, image, and document formats
WebP is a raster image format with its own support for quality, animation, or transparency. This card shows its role in “Media, image, and document formats” and a safe diagnostic path.
Open learning card →AVIF — Media, image, and document formats
AVIF is a media container that bundles supported video, audio, and metadata streams. This card shows its role in “Media, image, and document formats” and a safe diagnostic path.
Open learning card →GIF — Media, image, and document formats
GIF is a raster image format with its own support for quality, animation, or transparency. This card shows its role in “Media, image, and document formats” and a safe diagnostic path.
Open learning card →SVG — Media, image, and document formats
SVG describes shapes mathematically and remains sharp when enlarged. This card shows its role in “Media, image, and document formats” and a safe diagnostic path.
Open learning card →PDF — Media, image, and document formats
PDF preserves page layout or recovers text from scanned document pages. This card shows its role in “Media, image, and document formats” and a safe diagnostic path.
Open learning card →PDF page — Media, image, and document formats
PDF page preserves page layout or recovers text from scanned document pages. This card shows its role in “Media, image, and document formats” and a safe diagnostic path.
Open learning card →Raster image — Media, image, and document formats
Raster image stores an image as a finite pixel grid with fixed resolution. This card shows its role in “Media, image, and document formats” and a safe diagnostic path.
Open learning card →Vector graphic — Media, image, and document formats
Vector graphic describes shapes mathematically and remains sharp when enlarged. This card shows its role in “Media, image, and document formats” and a safe diagnostic path.
Open learning card →Alpha channel — Media, image, and document formats
Alpha channel stores per-pixel opacity in addition to color values. This card shows its role in “Media, image, and document formats” and a safe diagnostic path.
Open learning card →Transparency — Media, image, and document formats
Transparency stores per-pixel opacity in addition to color values. This card shows its role in “Media, image, and document formats” and a safe diagnostic path.
Open learning card →Image compression — Media, image, and document formats
Image compression reduces image data without information loss or by discarding detail in a controlled way. This card shows its role in “Media, image, and document formats” and a safe diagnostic path.
Open learning card →Lossless compression — Media, image, and document formats
Lossless compression reduces image data without information loss or by discarding detail in a controlled way. This card shows its role in “Media, image, and document formats” and a safe diagnostic path.
Open learning card →Lossy compression — Media, image, and document formats
Lossy compression reduces image data without information loss or by discarding detail in a controlled way. This card shows its role in “Media, image, and document formats” and a safe diagnostic path.
Open learning card →Metadata — Media, image, and document formats
Metadata stores extra information such as capture time, orientation, or device model outside the pixels. This card shows its role in “Media, image, and document formats” and a safe diagnostic path.
Open learning card →EXIF — Media, image, and document formats
EXIF stores extra information such as capture time, orientation, or device model outside the pixels. This card shows its role in “Media, image, and document formats” and a safe diagnostic path.
Open learning card →ICC color profile — Media, image, and document formats
ICC color profile maps numeric color values to a defined color space for consistent display. This card shows its role in “Media, image, and document formats” and a safe diagnostic path.
Open learning card →DPI — Media, image, and document formats
DPI is print-density metadata and does not by itself change pixel dimensions. This card shows its role in “Media, image, and document formats” and a safe diagnostic path.
Open learning card →Audio channel — Media, image, and document formats
Audio channel is one discrete audio stream within mono, stereo, or multichannel sound. This card shows its role in “Media, image, and document formats” and a safe diagnostic path.
Open learning card →Sample rate — Media, image, and document formats
Sample rate states how many audio samples are stored per second. This card shows its role in “Media, image, and document formats” and a safe diagnostic path.
Open learning card →Bit depth — Media, image, and document formats
Bit depth determines the numeric range of each uncompressed audio sample. This card shows its role in “Media, image, and document formats” and a safe diagnostic path.
Open learning card →Document OCR — Media, image, and document formats
Document OCR preserves page layout or recovers text from scanned document pages. This card shows its role in “Media, image, and document formats” and a safe diagnostic path.
Open learning card →Level 2 · Module 23Machine learning fundamentalsFundamentals, operations, and troubleshooting for Machine learning fundamentals.32 terms
Artificial intelligence — Machine learning fundamentals
Artificial intelligence is the umbrella term for systems that automate tasks such as perception, reasoning, or planning. This card shows its role in “Machine learning fundamentals” and a safe diagnostic path.
Open learning card →Machine learning — Machine learning fundamentals
Machine learning derives decision rules from example data instead of programming every rule by hand. This card shows its role in “Machine learning fundamentals” and a safe diagnostic path.
Open learning card →Deep learning — Machine learning fundamentals
Deep learning uses many stacked neural layers to learn features directly from large datasets. This card shows its role in “Machine learning fundamentals” and a safe diagnostic path.
Open learning card →Neural network — Machine learning fundamentals
A neural network connects weighted computational units in layers and adjusts their weights from an error signal. This card shows its role in “Machine learning fundamentals” and a safe diagnostic path.
Open learning card →Model — Machine learning fundamentals
A model is the learned mathematical mapping that turns inputs into predictions or generated outputs after training. This card shows its role in “Machine learning fundamentals” and a safe diagnostic path.
Open learning card →Model weight — Machine learning fundamentals
A model weight is a learned numeric value that controls how strongly a signal affects another model component. This card shows its role in “Machine learning fundamentals” and a safe diagnostic path.
Open learning card →Parameter — Machine learning fundamentals
A parameter is a model value optimized during training; parameter count affects memory use and capacity. This card shows its role in “Machine learning fundamentals” and a safe diagnostic path.
Open learning card →Training — Machine learning fundamentals
Training repeatedly computes predictions, errors, and weight updates over example data. This card shows its role in “Machine learning fundamentals” and a safe diagnostic path.
Open learning card →Training data — Machine learning fundamentals
Training data are the examples from which a model learns patterns; selection and labeling shape its behavior. This card shows its role in “Machine learning fundamentals” and a safe diagnostic path.
Open learning card →Inference — Machine learning fundamentals
Inference runs an already trained model on new inputs without further weight updates. This card shows its role in “Machine learning fundamentals” and a safe diagnostic path.
Open learning card →Input — Machine learning fundamentals
An input is data encoded for a model, such as token IDs, normalized pixels, or audio samples. This card shows its role in “Machine learning fundamentals” and a safe diagnostic path.
Open learning card →Output — Machine learning fundamentals
An output is the raw or post-processed model result, such as logits, text tokens, an image tensor, or a transcript. This card shows its role in “Machine learning fundamentals” and a safe diagnostic path.
Open learning card →Tensor — Machine learning fundamentals
A tensor is a multidimensional numeric array with a data type and shape used by ML frameworks. This card shows its role in “Machine learning fundamentals” and a safe diagnostic path.
Open learning card →Batch — Machine learning fundamentals
A batch groups multiple examples into one computation and trades memory consumption for throughput. This card shows its role in “Machine learning fundamentals” and a safe diagnostic path.
Open learning card →Epoch — Machine learning fundamentals
An epoch is one complete pass through the dataset selected for training. This card shows its role in “Machine learning fundamentals” and a safe diagnostic path.
Open learning card →Learning rate — Machine learning fundamentals
The learning rate scales each optimization step; values that are too high destabilize learning, while low values slow it down. This card shows its role in “Machine learning fundamentals” and a safe diagnostic path.
Open learning card →Loss function — Machine learning fundamentals
A loss function expresses the difference between a model prediction and its training target as a number. This card shows its role in “Machine learning fundamentals” and a safe diagnostic path.
Open learning card →Optimizer — Machine learning fundamentals
An optimizer uses gradients and their history to calculate concrete model-weight updates. This card shows its role in “Machine learning fundamentals” and a safe diagnostic path.
Open learning card →Checkpoint — Machine learning fundamentals
A checkpoint stores model state and often optimizer state at a particular training or release point. This card shows its role in “Machine learning fundamentals” and a safe diagnostic path.
Open learning card →Model architecture — Machine learning fundamentals
A model architecture defines layer types, connections, and data flow and must match the checkpoint. This card shows its role in “Machine learning fundamentals” and a safe diagnostic path.
Open learning card →Base model — Machine learning fundamentals
A base model is a broadly trained starting point used directly or adapted to a task. This card shows its role in “Machine learning fundamentals” and a safe diagnostic path.
Open learning card →Fine-tuning — Machine learning fundamentals
Fine-tuning continues training an existing base model on a smaller task-specific dataset. This card shows its role in “Machine learning fundamentals” and a safe diagnostic path.
Open learning card →Quantization — Machine learning fundamentals
Quantization stores weights or activations with fewer bits, trading accuracy for memory and compute savings. This card shows its role in “Machine learning fundamentals” and a safe diagnostic path.
Open learning card →Distillation — Machine learning fundamentals
Distillation trains a smaller student model to imitate outputs or intermediate representations of a larger teacher. This card shows its role in “Machine learning fundamentals” and a safe diagnostic path.
Open learning card →Embedding — Machine learning fundamentals
An embedding maps discrete content to a dense numeric vector where similar content can be close together. This card shows its role in “Machine learning fundamentals” and a safe diagnostic path.
Open learning card →Token — Machine learning fundamentals
A token is the smallest unit produced by a tokenizer and is not necessarily a complete word. This card shows its role in “Machine learning fundamentals” and a safe diagnostic path.
Open learning card →Tokenizer — Machine learning fundamentals
A tokenizer splits text using a fixed vocabulary and deterministically maps pieces to token IDs. This card shows its role in “Machine learning fundamentals” and a safe diagnostic path.
Open learning card →Transformer — Machine learning fundamentals
A transformer processes sequences with attention and parallel feed-forward blocks rather than a purely recurrent loop. This card shows its role in “Machine learning fundamentals” and a safe diagnostic path.
Open learning card →Attention — Machine learning fundamentals
Attention weights relationships between sequence positions so relevant parts influence the current computation more strongly. This card shows its role in “Machine learning fundamentals” and a safe diagnostic path.
Open learning card →Language model — Machine learning fundamentals
A language model estimates probabilities over token sequences and generates text by repeatedly selecting the next token. This card shows its role in “Machine learning fundamentals” and a safe diagnostic path.
Open learning card →Large language model — Machine learning fundamentals
A large language model is a scaled-up language model with many parameters and broad pretraining. This card shows its role in “Machine learning fundamentals” and a safe diagnostic path.
Open learning card →Multimodal model — Machine learning fundamentals
A multimodal model processes or generates multiple modalities such as text, images, and audio in one pipeline. This card shows its role in “Machine learning fundamentals” and a safe diagnostic path.
Open learning card →Level 2 · Module 24Diffusion and ComfyUIFundamentals, operations, and troubleshooting for Diffusion and ComfyUI.32 terms
Diffusion model — Diffusion and ComfyUI
A diffusion model learns to remove noise step by step from a random state to generate data. This card shows its role in “Diffusion and ComfyUI” and a safe diagnostic path.
Open learning card →Forward diffusion — Diffusion and ComfyUI
Forward diffusion progressively adds noise to training data according to a defined schedule. This card shows its role in “Diffusion and ComfyUI” and a safe diagnostic path.
Open learning card →Reverse diffusion — Diffusion and ComfyUI
Reverse diffusion reconstructs a sample from noise step by step under control of the learned model. This card shows its role in “Diffusion and ComfyUI” and a safe diagnostic path.
Open learning card →Noise — Diffusion and ComfyUI
Noise is the random starting tensor whose values are determined by seed, shape, and data type. This card shows its role in “Diffusion and ComfyUI” and a safe diagnostic path.
Open learning card →Noise schedule — Diffusion and ComfyUI
The noise schedule defines how much noise each timestep adds or removes. This card shows its role in “Diffusion and ComfyUI” and a safe diagnostic path.
Open learning card →Latent space — Diffusion and ComfyUI
Latent space is a compressed feature representation in which many image models operate instead of using pixels. This card shows its role in “Diffusion and ComfyUI” and a safe diagnostic path.
Open learning card →VAE — Diffusion and ComfyUI
A variational autoencoder compresses images into latents and decodes latents back into pixels. This card shows its role in “Diffusion and ComfyUI” and a safe diagnostic path.
Open learning card →Text encoder — Diffusion and ComfyUI
A text encoder turns prompt tokens into contextual vectors that condition image generation. This card shows its role in “Diffusion and ComfyUI” and a safe diagnostic path.
Open learning card →CLIP — Diffusion and ComfyUI
CLIP learns a shared image-text space and commonly provides text conditioning in diffusion pipelines. This card shows its role in “Diffusion and ComfyUI” and a safe diagnostic path.
Open learning card →Prompt — Diffusion and ComfyUI
A prompt describes desired subjects, properties, and relationships as positive conditioning for the generator. This card shows its role in “Diffusion and ComfyUI” and a safe diagnostic path.
Open learning card →Negative prompt — Diffusion and ComfyUI
A negative prompt provides unwanted properties as counter-conditioning when the selected model supports it. This card shows its role in “Diffusion and ComfyUI” and a safe diagnostic path.
Open learning card →Sampler — Diffusion and ComfyUI
A sampler is the numerical method that calculates the next latent state from model predictions. This card shows its role in “Diffusion and ComfyUI” and a safe diagnostic path.
Open learning card →Scheduler — Diffusion and ComfyUI
A scheduler distributes noise levels or sigmas across sampling steps, changing the trajectory and result. This card shows its role in “Diffusion and ComfyUI” and a safe diagnostic path.
Open learning card →Sampling steps — Diffusion and ComfyUI
Sampling steps are the number of iterative denoising computations; more steps are not automatically better. This card shows its role in “Diffusion and ComfyUI” and a safe diagnostic path.
Open learning card →Guidance scale — Diffusion and ComfyUI
Guidance scale controls how strongly conditional and unconditional predictions are separated. This card shows its role in “Diffusion and ComfyUI” and a safe diagnostic path.
Open learning card →CFG — Diffusion and ComfyUI
Classifier-free guidance combines conditional and unconditional model predictions to control prompt adherence. This card shows its role in “Diffusion and ComfyUI” and a safe diagnostic path.
Open learning card →Seed — Diffusion and ComfyUI
The seed initializes the random-number generator and makes identical inputs reproducible under identical conditions. This card shows its role in “Diffusion and ComfyUI” and a safe diagnostic path.
Open learning card →Denoising strength — Diffusion and ComfyUI
Denoising strength determines how far the starting latent is noised and therefore changed in image-to-image workflows. This card shows its role in “Diffusion and ComfyUI” and a safe diagnostic path.
Open learning card →Text-to-image — Diffusion and ComfyUI
Text-to-image creates an image latent from text conditioning and random noise without an input image. This card shows its role in “Diffusion and ComfyUI” and a safe diagnostic path.
Open learning card →Image-to-image — Diffusion and ComfyUI
Image-to-image encodes a source image as a latent and modifies it under additional prompt conditioning. This card shows its role in “Diffusion and ComfyUI” and a safe diagnostic path.
Open learning card →Inpainting — Diffusion and ComfyUI
Inpainting regenerates only a masked image region while using the unmasked context. This card shows its role in “Diffusion and ComfyUI” and a safe diagnostic path.
Open learning card →Outpainting — Diffusion and ComfyUI
Outpainting expands the canvas and generates new areas that match the existing edge context. This card shows its role in “Diffusion and ComfyUI” and a safe diagnostic path.
Open learning card →Upscaling — Diffusion and ComfyUI
Upscaling enlarges an image and reconstructs detail through interpolation or a learned model. This card shows its role in “Diffusion and ComfyUI” and a safe diagnostic path.
Open learning card →ControlNet — Diffusion and ComfyUI
ControlNet adds spatial guidance such as edges, pose, depth, or segmentation to a diffusion model. This card shows its role in “Diffusion and ComfyUI” and a safe diagnostic path.
Open learning card →LoRA — Diffusion and ComfyUI
LoRA stores a small low-rank weight update that adapts a base model without a full new checkpoint. This card shows its role in “Diffusion and ComfyUI” and a safe diagnostic path.
Open learning card →ComfyUI — Diffusion and ComfyUI
ComfyUI is a node-based interface and API that executes generative-model components as a directed workflow. This card shows its role in “Diffusion and ComfyUI” and a safe diagnostic path.
Open learning card →ComfyUI node — Diffusion and ComfyUI
A ComfyUI node has typed inputs and outputs and performs one bounded processing step. This card shows its role in “Diffusion and ComfyUI” and a safe diagnostic path.
Open learning card →ComfyUI workflow — Diffusion and ComfyUI
A ComfyUI workflow is a directed graph of compatible nodes including parameters and connections. This card shows its role in “Diffusion and ComfyUI” and a safe diagnostic path.
Open learning card →Workflow JSON — Diffusion and ComfyUI
Workflow JSON serializes node types, IDs, parameters, and edges for reproducible ComfyUI execution. This card shows its role in “Diffusion and ComfyUI” and a safe diagnostic path.
Open learning card →Model loader — Diffusion and ComfyUI
A model loader reads weights and matching architecture components from the model directory into memory. This card shows its role in “Diffusion and ComfyUI” and a safe diagnostic path.
Open learning card →KSampler — Diffusion and ComfyUI
KSampler is the ComfyUI node that combines latent, conditioning, sampler, scheduler, seed, and step count. This card shows its role in “Diffusion and ComfyUI” and a safe diagnostic path.
Open learning card →VAE Decode — Diffusion and ComfyUI
VAE Decode converts a completed latent tensor into visible pixels using the matching VAE. This card shows its role in “Diffusion and ComfyUI” and a safe diagnostic path.
Open learning card →Level 3 · Module 25Image models and model operationsFundamentals, operations, and troubleshooting for Image models and model operations.32 terms
FLUX — Image models and model operations
FLUX is a family of transformer-based image-generation models from Black Forest Labs with distinct workflow and licensing requirements. This card shows its role in “Image models and model operations” and a safe diagnostic path.
Open learning card →FLUX Schnell — Image models and model operations
FLUX Schnell is the FLUX variant optimized for few-step, fast inference and is governed by its own model license. This card shows its role in “Image models and model operations” and a safe diagnostic path.
Open learning card →FLUX Dev — Image models and model operations
FLUX Dev is a higher-quality, more compute-intensive FLUX variant whose non-commercial license must be reviewed before use. This card shows its role in “Image models and model operations” and a safe diagnostic path.
Open learning card →Quantized image model — Image models and model operations
A quantized image model lowers weight bit width to fit in less VRAM but may lose detail. This card shows its role in “Image models and model operations” and a safe diagnostic path.
Open learning card →GGUF model — Image models and model operations
A GGUF model bundles quantized tensors and metadata in a file format readable by compatible loaders. This card shows its role in “Image models and model operations” and a safe diagnostic path.
Open learning card →Safetensors — Image models and model operations
Safetensors is a weight format without executable pickle code and with explicit tensor offsets. This card shows its role in “Image models and model operations” and a safe diagnostic path.
Open learning card →Diffusers — Image models and model operations
Diffusers is a Python library providing model components, schedulers, and pipelines for diffusion inference. This card shows its role in “Image models and model operations” and a safe diagnostic path.
Open learning card →Hugging Face Hub — Image models and model operations
The Hugging Face Hub distributes versioned model artifacts, model cards, and licenses through repositories. This card shows its role in “Image models and model operations” and a safe diagnostic path.
Open learning card →Model card — Image models and model operations
A model card documents a model's purpose, training context, limitations, license, and known risks. This card shows its role in “Image models and model operations” and a safe diagnostic path.
Open learning card →Model license — Image models and model operations
A model license defines whether weights may be copied, modified, used commercially, or offered as a service. This card shows its role in “Image models and model operations” and a safe diagnostic path.
Open learning card →Commercial use — Image models and model operations
Commercial use means employing a model or its outputs in an activity intended to generate revenue. This card shows its role in “Image models and model operations” and a safe diagnostic path.
Open learning card →Checkpoint directory — Image models and model operations
The checkpoint directory is the loader's expected location for weight files and associated configuration. This card shows its role in “Image models and model operations” and a safe diagnostic path.
Open learning card →Model download — Image models and model operations
A model download transfers large versioned artifacts and must account for licensing, free space, and checksums. This card shows its role in “Image models and model operations” and a safe diagnostic path.
Open learning card →File integrity — Image models and model operations
File integrity uses a cryptographic checksum to confirm that a model artifact arrived complete and unchanged. This card shows its role in “Image models and model operations” and a safe diagnostic path.
Open learning card →Model cache — Image models and model operations
A model cache retains loaded or downloaded artifacts, saving time at the cost of RAM or disk space. This card shows its role in “Image models and model operations” and a safe diagnostic path.
Open learning card →VRAM requirement — Image models and model operations
VRAM requirement includes weights, activations, latents, and temporary buffers and depends on precision and resolution. This card shows its role in “Image models and model operations” and a safe diagnostic path.
Open learning card →Native resolution — Image models and model operations
Native resolution is the size range used during training where an image model usually keeps compositions stable. This card shows its role in “Image models and model operations” and a safe diagnostic path.
Open learning card →Aspect-ratio bucket — Image models and model operations
An aspect-ratio bucket groups training or inference sizes with similar ratios under bounded pixel budgets. This card shows its role in “Image models and model operations” and a safe diagnostic path.
Open learning card →Tiled upscaling — Image models and model operations
Tiled upscaling processes overlapping image tiles separately to reach high resolutions with limited VRAM. This card shows its role in “Image models and model operations” and a safe diagnostic path.
Open learning card →Real-ESRGAN — Image models and model operations
Real-ESRGAN is a learned super-resolution model that enlarges images and compensates for common real-world degradation. This card shows its role in “Image models and model operations” and a safe diagnostic path.
Open learning card →Background removal — Image models and model operations
Background removal segments the main subject and turns the result into a transparent alpha channel. This card shows its role in “Image models and model operations” and a safe diagnostic path.
Open learning card →Image segmentation — Image models and model operations
Image segmentation assigns a class or instance to each pixel, producing spatial regions. This card shows its role in “Image models and model operations” and a safe diagnostic path.
Open learning card →Segmentation mask — Image models and model operations
A segmentation mask encodes per pixel which region should be selected, protected, or modified. This card shows its role in “Image models and model operations” and a safe diagnostic path.
Open learning card →Object detection — Image models and model operations
Object detection returns classes and bounding boxes for detected objects but not a pixel-accurate mask. This card shows its role in “Image models and model operations” and a safe diagnostic path.
Open learning card →Object removal — Image models and model operations
Object removal masks a subject and reconstructs the hidden background through inpainting. This card shows its role in “Image models and model operations” and a safe diagnostic path.
Open learning card →Inpainting mask — Image models and model operations
An inpainting mask marks pixels to regenerate while preserving the rest of the image. This card shows its role in “Image models and model operations” and a safe diagnostic path.
Open learning card →Mask feathering — Image models and model operations
Mask feathering softens a hard mask edge over a chosen radius to hide transitions. This card shows its role in “Image models and model operations” and a safe diagnostic path.
Open learning card →Bounding box — Image models and model operations
A bounding box is a rectangular coordinate region describing a detected object's position and extent. This card shows its role in “Image models and model operations” and a safe diagnostic path.
Open learning card →Prompt weighting — Image models and model operations
Prompt weighting changes the relative influence of individual text fragments on image conditioning. This card shows its role in “Image models and model operations” and a safe diagnostic path.
Open learning card →Clip skip — Image models and model operations
CLIP skip uses an earlier text-encoder layer, changing prompt representation for models trained for it. This card shows its role in “Image models and model operations” and a safe diagnostic path.
Open learning card →LoRA weight — Image models and model operations
LoRA weight scales how strongly a loaded LoRA update affects the base model. This card shows its role in “Image models and model operations” and a safe diagnostic path.
Open learning card →Model switching — Image models and model operations
Model switching replaces weights and sometimes encoders or VAE; incompatible leftover components must be unloaded. This card shows its role in “Image models and model operations” and a safe diagnostic path.
Open learning card →Level 3 · Module 26Audio, transcription, and music generationFundamentals, operations, and troubleshooting for Audio, transcription, and music generation.32 terms
Speech recognition — Audio, transcription, and music generation
Speech recognition converts acoustic speech signals into text or token sequences. This card shows its role in “Audio, transcription, and music generation” and a safe diagnostic path.
Open learning card →Transcription — Audio, transcription, and music generation
Transcription produces readable text from an audio recording and may add timestamps or speaker information. This card shows its role in “Audio, transcription, and music generation” and a safe diagnostic path.
Open learning card →Whisper — Audio, transcription, and music generation
Whisper is an open model family for multilingual speech recognition, translation, and speech activity detection. This card shows its role in “Audio, transcription, and music generation” and a safe diagnostic path.
Open learning card →faster-whisper — Audio, transcription, and music generation
faster-whisper runs Whisper models through CTranslate2 with optimized data types and reduced memory use. This card shows its role in “Audio, transcription, and music generation” and a safe diagnostic path.
Open learning card →Whisper model size — Audio, transcription, and music generation
Whisper model size determines parameter count, language accuracy, VRAM demand, and processing speed. This card shows its role in “Audio, transcription, and music generation” and a safe diagnostic path.
Open learning card →Language detection — Audio, transcription, and music generation
Language detection estimates the likely spoken language from an audio segment for subsequent decoding. This card shows its role in “Audio, transcription, and music generation” and a safe diagnostic path.
Open learning card →Timestamp — Audio, transcription, and music generation
A timestamp maps text or an event to a position on the audio timeline. This card shows its role in “Audio, transcription, and music generation” and a safe diagnostic path.
Open learning card →Segment — Audio, transcription, and music generation
A transcription segment groups a continuous audio interval with text, start, end, and confidence. This card shows its role in “Audio, transcription, and music generation” and a safe diagnostic path.
Open learning card →Word timestamp — Audio, transcription, and music generation
A word timestamp estimates the start and end of one recognized word rather than an entire segment. This card shows its role in “Audio, transcription, and music generation” and a safe diagnostic path.
Open learning card →Voice activity detection — Audio, transcription, and music generation
Voice activity detection separates speech regions from silence or noise and reduces unnecessary inference. This card shows its role in “Audio, transcription, and music generation” and a safe diagnostic path.
Open learning card →Diarization — Audio, transcription, and music generation
Diarization assigns speech segments to different speaker identities without needing their names. This card shows its role in “Audio, transcription, and music generation” and a safe diagnostic path.
Open learning card →Speaker segmentation — Audio, transcription, and music generation
Speaker segmentation determines time boundaries where a different speaker begins or ends. This card shows its role in “Audio, transcription, and music generation” and a safe diagnostic path.
Open learning card →Subtitle — Audio, transcription, and music generation
A subtitle connects text to time intervals and optionally formatting or positioning information. This card shows its role in “Audio, transcription, and music generation” and a safe diagnostic path.
Open learning card →SRT — Audio, transcription, and music generation
SRT is a simple subtitle format containing an index, time interval, and text block. This card shows its role in “Audio, transcription, and music generation” and a safe diagnostic path.
Open learning card →WebVTT — Audio, transcription, and music generation
WebVTT is a web subtitle format with timestamps, cues, and optional presentation settings. This card shows its role in “Audio, transcription, and music generation” and a safe diagnostic path.
Open learning card →Text normalization — Audio, transcription, and music generation
Text normalization standardizes numbers, punctuation, capitalization, or filler words after recognition. This card shows its role in “Audio, transcription, and music generation” and a safe diagnostic path.
Open learning card →Audio resampling — Audio, transcription, and music generation
Audio resampling changes a signal's sample rate and must prevent aliasing with suitable filters. This card shows its role in “Audio, transcription, and music generation” and a safe diagnostic path.
Open learning card →Mono downmix — Audio, transcription, and music generation
A mono downmix combines multiple audio channels into one while avoiding clipping. This card shows its role in “Audio, transcription, and music generation” and a safe diagnostic path.
Open learning card →Noise reduction — Audio, transcription, and music generation
Noise reduction estimates unwanted signal components and attenuates them, potentially damaging speech or music. This card shows its role in “Audio, transcription, and music generation” and a safe diagnostic path.
Open learning card →Music generation — Audio, transcription, and music generation
Music generation creates audio from conditioning such as style, lyrics, structure, tempo, or reference material. This card shows its role in “Audio, transcription, and music generation” and a safe diagnostic path.
Open learning card →Text-to-music — Audio, transcription, and music generation
Text-to-music converts a textual style and content description into a temporal music representation and audio. This card shows its role in “Audio, transcription, and music generation” and a safe diagnostic path.
Open learning card →Lyrics — Audio, transcription, and music generation
Lyrics are sung text and often need section and line structure for a music model. This card shows its role in “Audio, transcription, and music generation” and a safe diagnostic path.
Open learning card →Instrumental mode — Audio, transcription, and music generation
Instrumental mode disables vocal conditioning and generates music without an intended voice. This card shows its role in “Audio, transcription, and music generation” and a safe diagnostic path.
Open learning card →Style description — Audio, transcription, and music generation
A style description conditions genre, instrumentation, mood, production, and vocal characteristics. This card shows its role in “Audio, transcription, and music generation” and a safe diagnostic path.
Open learning card →Song structure — Audio, transcription, and music generation
Song structure describes temporal sections such as intro, verse, chorus, bridge, and outro. This card shows its role in “Audio, transcription, and music generation” and a safe diagnostic path.
Open learning card →Tempo — Audio, transcription, and music generation
Tempo is the perceived speed of a piece of music and is commonly expressed in beats per minute. This card shows its role in “Audio, transcription, and music generation” and a safe diagnostic path.
Open learning card →BPM — Audio, transcription, and music generation
BPM specifies the intended number of musical beats per minute and provides a concrete tempo reference. This card shows its role in “Audio, transcription, and music generation” and a safe diagnostic path.
Open learning card →Musical key — Audio, transcription, and music generation
Musical key describes the tonal center and scale material that organize pitches within a piece. This card shows its role in “Audio, transcription, and music generation” and a safe diagnostic path.
Open learning card →Duration — Audio, transcription, and music generation
Duration is the planned or actual length of an audio result on the timeline. This card shows its role in “Audio, transcription, and music generation” and a safe diagnostic path.
Open learning card →ACE-Step — Audio, transcription, and music generation
ACE-Step is an open music-generation model that turns text, lyrics, and structure into longer audio pieces. This card shows its role in “Audio, transcription, and music generation” and a safe diagnostic path.
Open learning card →Language-model backend — Audio, transcription, and music generation
A language-model backend creates or interprets text conditioning for downstream audio or music models. This card shows its role in “Audio, transcription, and music generation” and a safe diagnostic path.
Open learning card →Music checkpoint — Audio, transcription, and music generation
A music checkpoint contains learned weights for audio generation and must match the model configuration. This card shows its role in “Audio, transcription, and music generation” and a safe diagnostic path.
Open learning card →Level 3 · Module 27GPU, CUDA, and inference optimizationFundamentals, operations, and troubleshooting for GPU, CUDA, and inference optimization.32 terms
GPU compute — GPU, CUDA, and inference optimization
GPU compute uses many parallel execution units for large tensor operations instead of serial CPU execution. This card shows its role in “GPU, CUDA, and inference optimization” and a safe diagnostic path.
Open learning card →CUDA — GPU, CUDA, and inference optimization
CUDA is NVIDIA's programming and runtime platform for general computation on compatible GPUs. This card shows its role in “GPU, CUDA, and inference optimization” and a safe diagnostic path.
Open learning card →CUDA Toolkit — GPU, CUDA, and inference optimization
The CUDA Toolkit provides compilers, libraries, headers, and diagnostic tools for CUDA applications. This card shows its role in “GPU, CUDA, and inference optimization” and a safe diagnostic path.
Open learning card →CUDA driver — GPU, CUDA, and inference optimization
The CUDA-capable NVIDIA driver connects user libraries to the GPU and kernel and limits supported runtime versions. This card shows its role in “GPU, CUDA, and inference optimization” and a safe diagnostic path.
Open learning card →Compute capability — GPU, CUDA, and inference optimization
Compute capability identifies the hardware features and instructions supported by an NVIDIA GPU. This card shows its role in “GPU, CUDA, and inference optimization” and a safe diagnostic path.
Open learning card →NVIDIA Container Toolkit — GPU, CUDA, and inference optimization
The NVIDIA Container Toolkit injects driver libraries and GPU devices into Linux containers in a controlled way. This card shows its role in “GPU, CUDA, and inference optimization” and a safe diagnostic path.
Open learning card →NVIDIA runtime — GPU, CUDA, and inference optimization
The NVIDIA container runtime augments OCI startup with GPU devices and matching driver mounts. This card shows its role in “GPU, CUDA, and inference optimization” and a safe diagnostic path.
Open learning card →Default runtime — GPU, CUDA, and inference optimization
The default runtime is the container runtime used for new containers when none is explicitly selected. This card shows its role in “GPU, CUDA, and inference optimization” and a safe diagnostic path.
Open learning card →GPU device — GPU, CUDA, and inference optimization
A GPU device is the operating-system-exposed compute unit with its own ID, VRAM, and utilization. This card shows its role in “GPU, CUDA, and inference optimization” and a safe diagnostic path.
Open learning card →GPU passthrough — GPU, CUDA, and inference optimization
GPU passthrough assigns a physical GPU device or selected functions to a VM or container. This card shows its role in “GPU, CUDA, and inference optimization” and a safe diagnostic path.
Open learning card →NVIDIA_VISIBLE_DEVICES — GPU, CUDA, and inference optimization
NVIDIA_VISIBLE_DEVICES filters which GPU IDs an NVIDIA container runtime exposes inside a container. This card shows its role in “GPU, CUDA, and inference optimization” and a safe diagnostic path.
Open learning card →CUDA out of memory — GPU, CUDA, and inference optimization
CUDA out of memory means a GPU memory allocation could not be satisfied from available VRAM. This card shows its role in “GPU, CUDA, and inference optimization” and a safe diagnostic path.
Open learning card →VRAM fragmentation — GPU, CUDA, and inference optimization
VRAM fragmentation splits free memory into blocks too small for a large contiguous allocation. This card shows its role in “GPU, CUDA, and inference optimization” and a safe diagnostic path.
Open learning card →Model offloading — GPU, CUDA, and inference optimization
Model offloading moves model components not needed concurrently from VRAM to RAM or storage. This card shows its role in “GPU, CUDA, and inference optimization” and a safe diagnostic path.
Open learning card →CPU offloading — GPU, CUDA, and inference optimization
CPU offloading keeps selected weights or operations in system memory, reducing VRAM use at a speed cost. This card shows its role in “GPU, CUDA, and inference optimization” and a safe diagnostic path.
Open learning card →VAE offloading — GPU, CUDA, and inference optimization
VAE offloading moves the VAE encoder or decoder to CPU when not needed alongside the main model. This card shows its role in “GPU, CUDA, and inference optimization” and a safe diagnostic path.
Open learning card →Attention slicing — GPU, CUDA, and inference optimization
Attention slicing computes attention in smaller chunks to reduce peak VRAM consumption. This card shows its role in “GPU, CUDA, and inference optimization” and a safe diagnostic path.
Open learning card →Memory-efficient attention — GPU, CUDA, and inference optimization
Memory-efficient attention avoids fully materializing large attention matrices. This card shows its role in “GPU, CUDA, and inference optimization” and a safe diagnostic path.
Open learning card →FlashAttention — GPU, CUDA, and inference optimization
FlashAttention is an IO-aware attention kernel that reduces memory traffic and accelerates exact attention. This card shows its role in “GPU, CUDA, and inference optimization” and a safe diagnostic path.
Open learning card →xFormers — GPU, CUDA, and inference optimization
xFormers is a library of optimized transformer components including memory-efficient attention kernels. This card shows its role in “GPU, CUDA, and inference optimization” and a safe diagnostic path.
Open learning card →Mixed precision — GPU, CUDA, and inference optimization
Mixed precision combines data types of different widths to use tensor cores and memory more efficiently. This card shows its role in “GPU, CUDA, and inference optimization” and a safe diagnostic path.
Open learning card →FP32 — GPU, CUDA, and inference optimization
FP32 is 32-bit floating point with high range and precision but high memory and bandwidth demand. This card shows its role in “GPU, CUDA, and inference optimization” and a safe diagnostic path.
Open learning card →FP16 — GPU, CUDA, and inference optimization
FP16 is 16-bit floating point with low memory use but a narrower numeric range than FP32. This card shows its role in “GPU, CUDA, and inference optimization” and a safe diagnostic path.
Open learning card →BF16 — GPU, CUDA, and inference optimization
BF16 keeps FP32's exponent range but uses fewer mantissa bits and therefore less precision. This card shows its role in “GPU, CUDA, and inference optimization” and a safe diagnostic path.
Open learning card →INT8 — GPU, CUDA, and inference optimization
INT8 represents quantized values with eight integer bits and requires calibration or suitable scales. This card shows its role in “GPU, CUDA, and inference optimization” and a safe diagnostic path.
Open learning card →INT4 — GPU, CUDA, and inference optimization
INT4 represents quantized values with four bits, greatly saving memory at the cost of higher quantization error. This card shows its role in “GPU, CUDA, and inference optimization” and a safe diagnostic path.
Open learning card →Quantization error — GPU, CUDA, and inference optimization
Quantization error is the difference between an original value and its discrete low-bit representation. This card shows its role in “GPU, CUDA, and inference optimization” and a safe diagnostic path.
Open learning card →Tensor Core — GPU, CUDA, and inference optimization
A tensor core is a specialized GPU unit for fast matrix multiplication in supported data types. This card shows its role in “GPU, CUDA, and inference optimization” and a safe diagnostic path.
Open learning card →Batch size — GPU, CUDA, and inference optimization
Batch size is the number of examples processed together and affects VRAM, latency, and throughput. This card shows its role in “GPU, CUDA, and inference optimization” and a safe diagnostic path.
Open learning card →Inference latency — GPU, CUDA, and inference optimization
Inference latency is the time from a complete input to an available model output. This card shows its role in “GPU, CUDA, and inference optimization” and a safe diagnostic path.
Open learning card →Throughput — GPU, CUDA, and inference optimization
Throughput measures how many examples, tokens, or frames a system processes per unit time. This card shows its role in “GPU, CUDA, and inference optimization” and a safe diagnostic path.
Open learning card →GPU utilization — GPU, CUDA, and inference optimization
GPU utilization reports the share of time compute units are active, not the amount of allocated VRAM. This card shows its role in “GPU, CUDA, and inference optimization” and a safe diagnostic path.
Open learning card →Level 3 · Module 28Application securityFundamentals, operations, and troubleshooting for Application security.32 terms
Threat model — Application security
A threat model documents assets, attackers, trust boundaries, and realistic attack paths for a system. This card shows its role in “Application security” and a safe diagnostic path.
Open learning card →Attack surface — Application security
Attack surface comprises every publicly or internally reachable input, service, account, and dependency. This card shows its role in “Application security” and a safe diagnostic path.
Open learning card →Security boundary — Application security
A security boundary marks a transition where data, identities, or privileges must be validated again. This card shows its role in “Application security” and a safe diagnostic path.
Open learning card →Defense in depth — Application security
Defense in depth combines independent safeguards so one failed control does not immediately compromise the whole system. This card shows its role in “Application security” and a safe diagnostic path.
Open learning card →Secret management — Application security
Secret management creates, stores, distributes, and revokes credentials outside source code and images. This card shows its role in “Application security” and a safe diagnostic path.
Open learning card →Secret rotation — Application security
Secret rotation replaces credentials in a controlled sequence, updates consumers, and then revokes the old value. This card shows its role in “Application security” and a safe diagnostic path.
Open learning card →Credential leak — Application security
A credential leak exposes a password, token, or key through logs, code, image layers, or output. This card shows its role in “Application security” and a safe diagnostic path.
Open learning card →Input validation — Application security
Input validation accepts only data with the expected structure, length, type, and value range. This card shows its role in “Application security” and a safe diagnostic path.
Open learning card →Output encoding — Application security
Output encoding escapes data for its specific output context such as HTML, URL, or JavaScript. This card shows its role in “Application security” and a safe diagnostic path.
Open learning card →SQL injection — Application security
SQL injection inserts untrusted input into database commands; parameterized queries separate data from SQL code. This card shows its role in “Application security” and a safe diagnostic path.
Open learning card →Command injection — Application security
Command injection executes user input as part of a shell command; fixed argument arrays avoid interpretation. This card shows its role in “Application security” and a safe diagnostic path.
Open learning card →Path traversal — Application security
Path traversal uses path components such as dot-dot to escape an allowed base directory. This card shows its role in “Application security” and a safe diagnostic path.
Open learning card →Cross-site scripting — Application security
Cross-site scripting injects untrusted content into a page as active browser code. This card shows its role in “Application security” and a safe diagnostic path.
Open learning card →Server-side request forgery — Application security
SSRF makes a server fetch attacker-selected internal or external destinations. This card shows its role in “Application security” and a safe diagnostic path.
Open learning card →Unsafe file upload — Application security
Unsafe file upload accepts content, size, names, or formats without sufficient validation and isolation. This card shows its role in “Application security” and a safe diagnostic path.
Open learning card →MIME sniffing — Application security
MIME sniffing lets clients guess content type and may interpret uploaded data as active content. This card shows its role in “Application security” and a safe diagnostic path.
Open learning card →Zip bomb — Application security
A zip bomb is a highly compressed archive that consumes extreme storage or compute when expanded. This card shows its role in “Application security” and a safe diagnostic path.
Open learning card →Malware scan — Application security
A malware scan checks files or behavior against signatures and heuristics but cannot guarantee safety. This card shows its role in “Application security” and a safe diagnostic path.
Open learning card →Rate limiting — Application security
Rate limiting caps actions per identity, IP, or token within a time window. This card shows its role in “Application security” and a safe diagnostic path.
Open learning card →Abuse prevention — Application security
Abuse prevention combines quotas, reputation, anomaly detection, and moderation against misuse. This card shows its role in “Application security” and a safe diagnostic path.
Open learning card →Denial of service — Application security
Denial of service deliberately exhausts a service's bandwidth, connections, CPU, GPU, RAM, or storage. This card shows its role in “Application security” and a safe diagnostic path.
Open learning card →Content Security Policy — Application security
Content Security Policy uses an HTTP header to restrict the sources from which a browser may load scripts and other resources. This card shows its role in “Application security” and a safe diagnostic path.
Open learning card →CORS policy — Application security
A CORS policy decides which foreign browser origins may read an API's responses. This card shows its role in “Application security” and a safe diagnostic path.
Open learning card →TLS termination — Application security
TLS termination decrypts HTTPS at a designated proxy and forwards the request under controlled conditions. This card shows its role in “Application security” and a safe diagnostic path.
Open learning card →Reverse-proxy trust — Application security
Reverse-proxy trust defines which proxies may supply forwarded client-IP and protocol headers. This card shows its role in “Application security” and a safe diagnostic path.
Open learning card →Security header — Application security
A security header controls browser protections such as framing, MIME handling, transport, or referrer disclosure. This card shows its role in “Application security” and a safe diagnostic path.
Open learning card →Audit log — Application security
An audit log records security-relevant actions with time, actor, target, and outcome for accountability. This card shows its role in “Application security” and a safe diagnostic path.
Open learning card →Data protection — Application security
Data protection safeguards personal data through legal basis, purpose limitation, access control, and secure processing. This card shows its role in “Application security” and a safe diagnostic path.
Open learning card →Data minimization — Application security
Data minimization collects and retains only data genuinely required for the stated purpose. This card shows its role in “Application security” and a safe diagnostic path.
Open learning card →Deletion policy — Application security
A deletion policy defines triggers, deadlines, scope, and verifiable execution of data deletion. This card shows its role in “Application security” and a safe diagnostic path.
Open learning card →Security update — Application security
A security update fixes a known vulnerability in software, an image, a library, or firmware. This card shows its role in “Application security” and a safe diagnostic path.
Open learning card →Vulnerability management — Application security
Vulnerability management inventories components, assesses findings, prioritizes risk, and tracks remediation. This card shows its role in “Application security” and a safe diagnostic path.
Open learning card →Level 3 · Module 29Reliability and capacity planningFundamentals, operations, and troubleshooting for Reliability and capacity planning.32 terms
Service-level indicator — Reliability and capacity planning
A service-level indicator is a measured value such as success rate or latency that represents user experience. This card shows its role in “Reliability and capacity planning” and a safe diagnostic path.
Open learning card →Service-level objective — Reliability and capacity planning
A service-level objective sets the target range for an SLI over a period. This card shows its role in “Reliability and capacity planning” and a safe diagnostic path.
Open learning card →Service-level agreement — Reliability and capacity planning
A service-level agreement is a contractual promise with defined measurement rules and possible consequences for failure. This card shows its role in “Reliability and capacity planning” and a safe diagnostic path.
Open learning card →Error budget — Reliability and capacity planning
An error budget is the tolerable amount of failure or unavailable time derived from an SLO. This card shows its role in “Reliability and capacity planning” and a safe diagnostic path.
Open learning card →Capacity planning — Reliability and capacity planning
Capacity planning forecasts load and sizes compute, storage, networking, and headroom. This card shows its role in “Reliability and capacity planning” and a safe diagnostic path.
Open learning card →Resource profile — Reliability and capacity planning
A resource profile measures a workload's typical and peak CPU, RAM, GPU, disk, and network use. This card shows its role in “Reliability and capacity planning” and a safe diagnostic path.
Open learning card →CPU limit — Reliability and capacity planning
A CPU limit caps processor time available to a container and may throttle it when reached. This card shows its role in “Reliability and capacity planning” and a safe diagnostic path.
Open learning card →Memory limit — Reliability and capacity planning
A memory limit caps RAM for a process or container; exceeding it may trigger an OOM termination. This card shows its role in “Reliability and capacity planning” and a safe diagnostic path.
Open learning card →GPU limit — Reliability and capacity planning
A GPU limit restricts device access or planned GPU capacity but is not supported uniformly by every orchestrator. This card shows its role in “Reliability and capacity planning” and a safe diagnostic path.
Open learning card →Disk limit — Reliability and capacity planning
A disk limit caps occupied storage or reserves free space for safe operation. This card shows its role in “Reliability and capacity planning” and a safe diagnostic path.
Open learning card →Upload quota — Reliability and capacity planning
An upload quota caps the number or total size of files uploaded per user or period. This card shows its role in “Reliability and capacity planning” and a safe diagnostic path.
Open learning card →Daily quota — Reliability and capacity planning
A daily quota caps usage during one calendar day and resets its counter at a defined time and timezone. This card shows its role in “Reliability and capacity planning” and a safe diagnostic path.
Open learning card →Concurrency — Reliability and capacity planning
Concurrency means multiple tasks are in progress at once even if they do not compute in parallel. This card shows its role in “Reliability and capacity planning” and a safe diagnostic path.
Open learning card →Parallelism — Reliability and capacity planning
Parallelism executes multiple operations simultaneously on different compute units. This card shows its role in “Reliability and capacity planning” and a safe diagnostic path.
Open learning card →Job serialization — Reliability and capacity planning
Job serialization runs resource-intensive jobs one after another to avoid load spikes. This card shows its role in “Reliability and capacity planning” and a safe diagnostic path.
Open learning card →Queue position — Reliability and capacity planning
Queue position is the number of jobs scheduled ahead of one job and may change due to priorities. This card shows its role in “Reliability and capacity planning” and a safe diagnostic path.
Open learning card →Wait time — Reliability and capacity planning
Wait time measures the interval between job acceptance and processing start. This card shows its role in “Reliability and capacity planning” and a safe diagnostic path.
Open learning card →Processing speed — Reliability and capacity planning
Processing speed relates completed data volume or work units to elapsed time for a defined workload. This card shows its role in “Reliability and capacity planning” and a safe diagnostic path.
Open learning card →Autoscaling — Reliability and capacity planning
Autoscaling changes instance count or resources automatically from measured load and defined bounds. This card shows its role in “Reliability and capacity planning” and a safe diagnostic path.
Open learning card →Vertical scaling — Reliability and capacity planning
Vertical scaling assigns more or less CPU, RAM, or GPU to an existing instance. This card shows its role in “Reliability and capacity planning” and a safe diagnostic path.
Open learning card →Horizontal scaling — Reliability and capacity planning
Horizontal scaling changes the number of equivalent instances and requires shareable state. This card shows its role in “Reliability and capacity planning” and a safe diagnostic path.
Open learning card →Load shedding — Reliability and capacity planning
Load shedding deliberately rejects lower-priority work before overload harms every request. This card shows its role in “Reliability and capacity planning” and a safe diagnostic path.
Open learning card →Circuit breaker — Reliability and capacity planning
A circuit breaker temporarily stops calls to a failing dependency and later probes for recovery. This card shows its role in “Reliability and capacity planning” and a safe diagnostic path.
Open learning card →Retry budget — Reliability and capacity planning
A retry budget caps extra attempts so failures are not amplified by a retry storm. This card shows its role in “Reliability and capacity planning” and a safe diagnostic path.
Open learning card →Exponential backoff — Reliability and capacity planning
Exponential backoff increases delay between retries and is usually combined with random jitter. This card shows its role in “Reliability and capacity planning” and a safe diagnostic path.
Open learning card →Timeout budget — Reliability and capacity planning
A timeout budget divides maximum end-to-end time among internal calls and processing. This card shows its role in “Reliability and capacity planning” and a safe diagnostic path.
Open learning card →Graceful shutdown — Reliability and capacity planning
Graceful shutdown stops accepting new work, finishes in-flight tasks, and releases resources cleanly. This card shows its role in “Reliability and capacity planning” and a safe diagnostic path.
Open learning card →Health dependency — Reliability and capacity planning
A health dependency is an external component whose state affects a service's readiness. This card shows its role in “Reliability and capacity planning” and a safe diagnostic path.
Open learning card →Single point of failure — Reliability and capacity planning
A single point of failure is one component whose failure stops the entire service. This card shows its role in “Reliability and capacity planning” and a safe diagnostic path.
Open learning card →High availability — Reliability and capacity planning
High availability uses redundancy and automatic failover to survive individual failures. This card shows its role in “Reliability and capacity planning” and a safe diagnostic path.
Open learning card →Disaster recovery — Reliability and capacity planning
Disaster recovery restores data and services from tested backups after a major failure. This card shows its role in “Reliability and capacity planning” and a safe diagnostic path.
Open learning card →Recovery time objective — Reliability and capacity planning
Recovery time objective is the maximum acceptable time to restore a service. This card shows its role in “Reliability and capacity planning” and a safe diagnostic path.
Open learning card →Level 3 · Module 30Builds, tests, and releasesFundamentals, operations, and troubleshooting for Builds, tests, and releases.32 terms
Source code — Builds, tests, and releases
Source code is the human-readable instruction from which a build creates executable or distributable artifacts. This card shows its role in “Builds, tests, and releases” and a safe diagnostic path.
Open learning card →Version control — Builds, tests, and releases
Version control records traceable file changes and enables comparison, collaboration, and restoration. This card shows its role in “Builds, tests, and releases” and a safe diagnostic path.
Open learning card →Git — Builds, tests, and releases
Git is a distributed version-control system that stores content as immutable objects and commits. This card shows its role in “Builds, tests, and releases” and a safe diagnostic path.
Open learning card →Repository — Builds, tests, and releases
A repository contains the version history, references, and working data of a bounded project. This card shows its role in “Builds, tests, and releases” and a safe diagnostic path.
Open learning card →Commit — Builds, tests, and releases
A commit is an immutable snapshot with a parent reference, author information, and message. This card shows its role in “Builds, tests, and releases” and a safe diagnostic path.
Open learning card →Branch — Builds, tests, and releases
A branch is a movable name for a line of commits and enables parallel development. This card shows its role in “Builds, tests, and releases” and a safe diagnostic path.
Open learning card →Tag — Builds, tests, and releases
A Git tag is a stable reference to a particular commit, commonly used for releases. This card shows its role in “Builds, tests, and releases” and a safe diagnostic path.
Open learning card →Merge — Builds, tests, and releases
A merge combines changes from two commit lines and requires conflict resolution for overlapping edits. This card shows its role in “Builds, tests, and releases” and a safe diagnostic path.
Open learning card →Release — Builds, tests, and releases
A release is a named, verified bundle of version, artifacts, changes, and notes. This card shows its role in “Builds, tests, and releases” and a safe diagnostic path.
Open learning card →Semantic versioning — Builds, tests, and releases
Semantic versioning labels incompatible, compatible, and corrective changes as major, minor, and patch. This card shows its role in “Builds, tests, and releases” and a safe diagnostic path.
Open learning card →Changelog — Builds, tests, and releases
A changelog summarizes user-relevant changes between released versions in a structured form. This card shows its role in “Builds, tests, and releases” and a safe diagnostic path.
Open learning card →Build — Builds, tests, and releases
A build reproducibly transforms defined sources and dependencies into a distributable artifact. This card shows its role in “Builds, tests, and releases” and a safe diagnostic path.
Open learning card →Reproducible build — Builds, tests, and releases
A reproducible build creates a bit-identical or verifiably equivalent result from identical sources and tool versions. This card shows its role in “Builds, tests, and releases” and a safe diagnostic path.
Open learning card →Multi-stage build — Builds, tests, and releases
A multi-stage build separates compilation tools from a lean runtime image and copies only required artifacts. This card shows its role in “Builds, tests, and releases” and a safe diagnostic path.
Open learning card →Build cache — Builds, tests, and releases
A build cache reuses unchanged intermediate results and invalidates them based on inputs. This card shows its role in “Builds, tests, and releases” and a safe diagnostic path.
Open learning card →.dockerignore — Builds, tests, and releases
A .dockerignore file excludes local files from the Docker build context. This card shows its role in “Builds, tests, and releases” and a safe diagnostic path.
Open learning card →Dependency lockfile — Builds, tests, and releases
A dependency lockfile pins exact resolved versions and integrity values for repeatable installations. This card shows its role in “Builds, tests, and releases” and a safe diagnostic path.
Open learning card →Unit test — Builds, tests, and releases
A unit test checks a small function or class in isolation with controlled inputs and outputs. This card shows its role in “Builds, tests, and releases” and a safe diagnostic path.
Open learning card →API test — Builds, tests, and releases
An API test sends defined requests and checks status, headers, schema, and business response. This card shows its role in “Builds, tests, and releases” and a safe diagnostic path.
Open learning card →End-to-end test — Builds, tests, and releases
An end-to-end test exercises a complete user flow across real integrated components. This card shows its role in “Builds, tests, and releases” and a safe diagnostic path.
Open learning card →Browser test — Builds, tests, and releases
A browser test drives a browser engine and checks DOM, interaction, navigation, and visible states. This card shows its role in “Builds, tests, and releases” and a safe diagnostic path.
Open learning card →Fixture — Builds, tests, and releases
A fixture is controlled starting data or system state used reproducibly by a test. This card shows its role in “Builds, tests, and releases” and a safe diagnostic path.
Open learning card →Mock — Builds, tests, and releases
A mock replaces a dependency and specifies expected calls or controlled responses. This card shows its role in “Builds, tests, and releases” and a safe diagnostic path.
Open learning card →Test coverage — Builds, tests, and releases
Test coverage measures which code paths a test run executes but does not prove correctness. This card shows its role in “Builds, tests, and releases” and a safe diagnostic path.
Open learning card →Linter — Builds, tests, and releases
A linter statically detects rule violations, suspicious patterns, and common source-code errors. This card shows its role in “Builds, tests, and releases” and a safe diagnostic path.
Open learning card →Formatter — Builds, tests, and releases
A formatter deterministically rewrites source code into an agreed style. This card shows its role in “Builds, tests, and releases” and a safe diagnostic path.
Open learning card →Static analysis — Builds, tests, and releases
Static analysis examines code without execution for type errors, data flows, vulnerabilities, or rule violations. This card shows its role in “Builds, tests, and releases” and a safe diagnostic path.
Open learning card →Continuous integration — Builds, tests, and releases
Continuous integration automatically builds and tests every change in a clean environment. This card shows its role in “Builds, tests, and releases” and a safe diagnostic path.
Open learning card →Continuous delivery — Builds, tests, and releases
Continuous delivery automatically prepares verified artifacts while keeping production release controllable. This card shows its role in “Builds, tests, and releases” and a safe diagnostic path.
Open learning card →Deployment artifact — Builds, tests, and releases
A deployment artifact is the immutable, versioned package rolled out to a target environment. This card shows its role in “Builds, tests, and releases” and a safe diagnostic path.
Open learning card →Checksum manifest — Builds, tests, and releases
A checksum manifest lists files and cryptographic hashes to verify transfer and content. This card shows its role in “Builds, tests, and releases” and a safe diagnostic path.
Open learning card →Staging — Builds, tests, and releases
Staging is a production-like environment for integration and release tests without real production data. This card shows its role in “Builds, tests, and releases” and a safe diagnostic path.
Open learning card →Level 3 · Module 31Incident analysis and recoveryFundamentals, operations, and troubleshooting for Incident analysis and recovery.32 terms
Incident — Incident analysis and recovery
An incident is an unplanned disruption affecting a service's security, availability, or quality. This card shows its role in “Incident analysis and recovery” and a safe diagnostic path.
Open learning card →Incident severity — Incident analysis and recovery
Incident severity classifies impact and urgency using predefined criteria. This card shows its role in “Incident analysis and recovery” and a safe diagnostic path.
Open learning card →Initial response — Incident analysis and recovery
Initial response acknowledges the incident, preserves evidence, limits harm, and assigns ownership. This card shows its role in “Incident analysis and recovery” and a safe diagnostic path.
Open learning card →Triage — Incident analysis and recovery
Triage prioritizes symptoms, affected users, and likely failure domains for the first checks. This card shows its role in “Incident analysis and recovery” and a safe diagnostic path.
Open learning card →Affected service — Incident analysis and recovery
An affected service is the component whose observable behavior differs from its expected state. This card shows its role in “Incident analysis and recovery” and a safe diagnostic path.
Open learning card →Blast radius — Incident analysis and recovery
Blast radius describes how many users, data sets, and dependent systems an incident reaches. This card shows its role in “Incident analysis and recovery” and a safe diagnostic path.
Open learning card →Incident timeline — Incident analysis and recovery
An incident timeline orders changes, alerts, symptoms, and actions chronologically with their time source. This card shows its role in “Incident analysis and recovery” and a safe diagnostic path.
Open learning card →Known change — Incident analysis and recovery
A known change is a documented modification shortly before the symptom and therefore a testable hypothesis. This card shows its role in “Incident analysis and recovery” and a safe diagnostic path.
Open learning card →Service inspect — Incident analysis and recovery
Service inspect shows a service's desired orchestrator specification including image, mounts, and environment. This card shows its role in “Incident analysis and recovery” and a safe diagnostic path.
Open learning card →Task history — Incident analysis and recovery
Task history shows current and previous instances of an orchestrated service with states and errors. This card shows its role in “Incident analysis and recovery” and a safe diagnostic path.
Open learning card →Container inspect — Incident analysis and recovery
Container inspect returns a container's actual runtime state as structured metadata. This card shows its role in “Incident analysis and recovery” and a safe diagnostic path.
Open learning card →Container exit code — Incident analysis and recovery
Container exit code is the main process's numeric return value and helps distinguish startup, signal, and application failures. This card shows its role in “Incident analysis and recovery” and a safe diagnostic path.
Open learning card →OOMKilled — Incident analysis and recovery
OOMKilled means the kernel or runtime terminated a process because of memory pressure. This card shows its role in “Incident analysis and recovery” and a safe diagnostic path.
Open learning card →Health-check failure — Incident analysis and recovery
A health-check failure occurs when the configured probe command does not respond successfully in time. This card shows its role in “Incident analysis and recovery” and a safe diagnostic path.
Open learning card →Restart loop — Incident analysis and recovery
A restart loop occurs when a service repeatedly starts, fails, and is restarted by policy. This card shows its role in “Incident analysis and recovery” and a safe diagnostic path.
Open learning card →Image pull failure — Incident analysis and recovery
An image-pull failure blocks startup because registry, reference, authorization, network, or platform is incompatible. This card shows its role in “Incident analysis and recovery” and a safe diagnostic path.
Open learning card →Bind-mount failure — Incident analysis and recovery
A bind-mount failure occurs when host path, type, permissions, or node placement does not match the specification. This card shows its role in “Incident analysis and recovery” and a safe diagnostic path.
Open learning card →Permission denied — Incident analysis and recovery
Permission denied means file mode, owner, security profile, or process identity forbids an operation. This card shows its role in “Incident analysis and recovery” and a safe diagnostic path.
Open learning card →Connection refused — Incident analysis and recovery
Connection refused means the target is reachable but no listener accepts the connection on the addressed port. This card shows its role in “Incident analysis and recovery” and a safe diagnostic path.
Open learning card →DNS failure — Incident analysis and recovery
A DNS failure prevents resolving a name to the address needed for a connection. This card shows its role in “Incident analysis and recovery” and a safe diagnostic path.
Open learning card →TLS failure — Incident analysis and recovery
A TLS failure occurs in certificate validation, hostname, protocol version, cipher, or trust chain. This card shows its role in “Incident analysis and recovery” and a safe diagnostic path.
Open learning card →HTTP 502 — Incident analysis and recovery
HTTP 502 means a gateway did not receive a valid response from its upstream. This card shows its role in “Incident analysis and recovery” and a safe diagnostic path.
Open learning card →HTTP 503 — Incident analysis and recovery
HTTP 503 means a service is temporarily unready or unavailable due to overload. This card shows its role in “Incident analysis and recovery” and a safe diagnostic path.
Open learning card →HTTP 504 — Incident analysis and recovery
HTTP 504 means a gateway did not receive an upstream response within its timeout. This card shows its role in “Incident analysis and recovery” and a safe diagnostic path.
Open learning card →Queue stall — Incident analysis and recovery
A queue stall occurs when waiting jobs grow but no worker successfully claims or completes them. This card shows its role in “Incident analysis and recovery” and a safe diagnostic path.
Open learning card →Worker crash — Incident analysis and recovery
A worker crash unexpectedly terminates the processing process during or before a job. This card shows its role in “Incident analysis and recovery” and a safe diagnostic path.
Open learning card →Database connection failure — Incident analysis and recovery
A database connection failure results from wrong addressing, authentication, TLS, pool exhaustion, or an unready server. This card shows its role in “Incident analysis and recovery” and a safe diagnostic path.
Open learning card →Disk full — Incident analysis and recovery
Disk full means the filesystem or inode pool cannot accept more writes. This card shows its role in “Incident analysis and recovery” and a safe diagnostic path.
Open learning card →GPU out of memory — Incident analysis and recovery
GPU out of memory means weights, activations, and buffers exceed available VRAM. This card shows its role in “Incident analysis and recovery” and a safe diagnostic path.
Open learning card →Rollback — Incident analysis and recovery
A rollback restores the last known working artifact, configuration, and schema version. This card shows its role in “Incident analysis and recovery” and a safe diagnostic path.
Open learning card →Service recovery — Incident analysis and recovery
Service recovery returns a disrupted service to a verified stable state in a controlled way. This card shows its role in “Incident analysis and recovery” and a safe diagnostic path.
Open learning card →Postmortem — Incident analysis and recovery
A postmortem documents impact, timeline, causes, and concrete improvements without blame. This card shows its role in “Incident analysis and recovery” and a safe diagnostic path.
Open learning card →Level 3 · Module 32Maintenance, updates, and governanceFundamentals, operations, and troubleshooting for Maintenance, updates, and governance.32 terms
Maintenance window — Maintenance, updates, and governance
A maintenance window is an announced period for changes with a defined start, end, and abort point. This card shows its role in “Maintenance, updates, and governance” and a safe diagnostic path.
Open learning card →Inventory — Maintenance, updates, and governance
An inventory lists operated hardware, software, versions, owners, and lifecycle status. This card shows its role in “Maintenance, updates, and governance” and a safe diagnostic path.
Open learning card →Service catalog — Maintenance, updates, and governance
A service catalog documents each service's purpose, owner, dependencies, interfaces, and operational requirements. This card shows its role in “Maintenance, updates, and governance” and a safe diagnostic path.
Open learning card →Dependency map — Maintenance, updates, and governance
A dependency map shows directed relationships among services, databases, networks, and external components. This card shows its role in “Maintenance, updates, and governance” and a safe diagnostic path.
Open learning card →Configuration baseline — Maintenance, updates, and governance
A configuration baseline is the verified reference state against which later changes are compared. This card shows its role in “Maintenance, updates, and governance” and a safe diagnostic path.
Open learning card →Desired configuration — Maintenance, updates, and governance
Desired configuration declaratively describes the state that automation or operations should establish. This card shows its role in “Maintenance, updates, and governance” and a safe diagnostic path.
Open learning card →Configuration drift — Maintenance, updates, and governance
Configuration drift is an unintended difference between actual state and versioned desired configuration. This card shows its role in “Maintenance, updates, and governance” and a safe diagnostic path.
Open learning card →Version check — Maintenance, updates, and governance
A version check determines installed and available versions together with channel and support status. This card shows its role in “Maintenance, updates, and governance” and a safe diagnostic path.
Open learning card →Release notes — Maintenance, updates, and governance
Release notes describe a version's changes, fixes, known issues, and upgrade guidance. This card shows its role in “Maintenance, updates, and governance” and a safe diagnostic path.
Open learning card →Breaking change — Maintenance, updates, and governance
A breaking change makes previously valid interfaces, configurations, or data incompatible without adaptation. This card shows its role in “Maintenance, updates, and governance” and a safe diagnostic path.
Open learning card →Deprecation — Maintenance, updates, and governance
Deprecation announces future removal of an available feature and identifies a replacement path. This card shows its role in “Maintenance, updates, and governance” and a safe diagnostic path.
Open learning card →Compatibility matrix — Maintenance, updates, and governance
A compatibility matrix records tested combinations of software, driver, model, and platform versions. This card shows its role in “Maintenance, updates, and governance” and a safe diagnostic path.
Open learning card →Migration plan — Maintenance, updates, and governance
A migration plan defines sequence, owners, checks, data paths, downtime, and rollback. This card shows its role in “Maintenance, updates, and governance” and a safe diagnostic path.
Open learning card →Data migration — Maintenance, updates, and governance
A data migration copies or transforms data between locations, formats, or systems with integrity checks. This card shows its role in “Maintenance, updates, and governance” and a safe diagnostic path.
Open learning card →Schema migration — Maintenance, updates, and governance
A schema migration changes database tables, fields, indexes, or constraints in a controlled way. This card shows its role in “Maintenance, updates, and governance” and a safe diagnostic path.
Open learning card →Model upgrade — Maintenance, updates, and governance
A model upgrade replaces weights or architecture and requires quality, resource, and workflow tests. This card shows its role in “Maintenance, updates, and governance” and a safe diagnostic path.
Open learning card →Driver upgrade — Maintenance, updates, and governance
A driver upgrade replaces the hardware-facing software layer and must keep kernel, runtime, and applications compatible. This card shows its role in “Maintenance, updates, and governance” and a safe diagnostic path.
Open learning card →Image upgrade — Maintenance, updates, and governance
An image upgrade deploys a new immutable container image instead of modifying a running container. This card shows its role in “Maintenance, updates, and governance” and a safe diagnostic path.
Open learning card →Canary deployment — Maintenance, updates, and governance
A canary deployment sends a small fraction of traffic to a new version first and compares signals. This card shows its role in “Maintenance, updates, and governance” and a safe diagnostic path.
Open learning card →Blue-green deployment — Maintenance, updates, and governance
Blue-green deployment runs old and new environments in parallel and switches traffic in a controlled way. This card shows its role in “Maintenance, updates, and governance” and a safe diagnostic path.
Open learning card →Pre-upgrade backup — Maintenance, updates, and governance
A pre-upgrade backup preserves all non-reproducible data and recovery metadata before a change. This card shows its role in “Maintenance, updates, and governance” and a safe diagnostic path.
Open learning card →Post-upgrade validation — Maintenance, updates, and governance
Post-upgrade validation repeats defined functional, data, and performance checks after a change. This card shows its role in “Maintenance, updates, and governance” and a safe diagnostic path.
Open learning card →Rollback point — Maintenance, updates, and governance
A rollback point is the uniquely named state to which artifacts, configuration, and data can return. This card shows its role in “Maintenance, updates, and governance” and a safe diagnostic path.
Open learning card →License review — Maintenance, updates, and governance
License review checks rights, obligations, and incompatibilities in software, model, and content licenses. This card shows its role in “Maintenance, updates, and governance” and a safe diagnostic path.
Open learning card →Open-source license — Maintenance, updates, and governance
An open-source license grants use, inspection, modification, and redistribution under defined conditions. This card shows its role in “Maintenance, updates, and governance” and a safe diagnostic path.
Open learning card →Data retention — Maintenance, updates, and governance
Data retention defines which data is stored, for what reason, and for how long. This card shows its role in “Maintenance, updates, and governance” and a safe diagnostic path.
Open learning card →Deletion request — Maintenance, updates, and governance
A deletion request is a traceable demand to locate and remove affected personal data. This card shows its role in “Maintenance, updates, and governance” and a safe diagnostic path.
Open learning card →Responsibility — Maintenance, updates, and governance
Responsibility assigns an accountable role for operations, release, security, and incident response. This card shows its role in “Maintenance, updates, and governance” and a safe diagnostic path.
Open learning card →Operations documentation — Maintenance, updates, and governance
Operations documentation covers architecture, dependencies, routines, thresholds, and recovery procedures. This card shows its role in “Maintenance, updates, and governance” and a safe diagnostic path.
Open learning card →Runbook — Maintenance, updates, and governance
A runbook is a step-by-step, verifiable procedure for a recurring operational or incident scenario. This card shows its role in “Maintenance, updates, and governance” and a safe diagnostic path.
Open learning card →Standard operating procedure — Maintenance, updates, and governance
A standard operating procedure defines mandatory steps, roles, evidence, and approvals for a routine process. This card shows its role in “Maintenance, updates, and governance” and a safe diagnostic path.
Open learning card →Technical debt — Maintenance, updates, and governance
Technical debt is intentionally or unintentionally deferred quality work that makes later changes more expensive. This card shows its role in “Maintenance, updates, and governance” and a safe diagnostic path.
Open learning card →No matching terms found.