Developer Glossary

A

ACID stub Atomicity, Consistency, Isolation, Durability , transaction guarantees of relational DBs.
API key stub Opaque secret used to authenticate a server-to-server API caller.
ASCII stub American Standard Code for Information Interchange , 7-bit character encoding.
AST stub Abstract Syntax Tree , tree representation of source code used by compilers and linters.

Base64 stub Text encoding that represents binary data using 64 printable ASCII characters.

Canonical URL stub The preferred URL for a piece of content, declared via `<link rel="canonical">`.
Canvas stub HTML `<canvas>` element , bitmap drawing surface driven by JavaScript.
Capture group stub Parenthesized sub-pattern in regex whose match can be referenced by number or name.
Chroma subsampling stub Image compression trick that stores color at a lower resolution than luminance.
CORS stub Cross-Origin Resource Sharing , browser policy that gates cross-domain HTTP calls.
CRLF stub Carriage Return + Line Feed (`\r\n`) , Windows-style line ending used in HTTP and email.
Cron expression stub Five-field syntax (`m h dom mon dow`) used to schedule recurring jobs on Unix.
CSRF stub Cross-Site Request Forgery , attack that tricks a logged-in user into submitting an action.
CSS Grid stub Two-dimensional CSS layout system that arranges items in rows and columns.
CSV stub Comma-Separated Values , simple tabular plaintext format.

Debounce stub Wrap a function so it only fires after a burst of calls has quieted for N ms.
DNS stub Domain Name System , maps domain names to IP addresses.
Docker stub Container runtime that packages an app and its dependencies into a portable image.
DOM stub Document Object Model , tree of nodes representing an HTML or XML document in the browser.

Flexbox stub One-dimensional CSS layout system that distributes space along a single axis.

Git stub Distributed version control system that tracks content-addressed snapshots of a tree.
GraphQL stub Query language and runtime that lets clients request exactly the fields they need.

Hex color stub Six-digit hexadecimal RGB color code (e.g. `#ff0000`) used in CSS and design tools.
HMAC stub Hash-based Message Authentication Code , keyed hash for verifying integrity + origin.
hreflang stub Link-tag attribute that tells search engines which language+region variant to show.
HTTP stub HyperText Transfer Protocol , the request-response protocol powering the web.
HTTPS stub HTTP over TLS , encrypted variant of HTTP that prevents eavesdropping.

Idempotent stub Property of an operation that produces the same result whether called once or many times.
ISO 8601 stub International date/time format (YYYY-MM-DDTHH:MM:SSZ) that avoids locale ambiguity.

JSON stub JavaScript Object Notation , a lightweight text format for structured data.
JWT stub JSON Web Token , compact signed token format for authentication claims.

Lookahead stub Regex assertion `(?=...)` that matches without consuming characters.

Markdown stub Lightweight plain-text format that converts to HTML, used for docs and READMEs.
MD5 stub Message-Digest 5 , 128-bit hash function, cryptographically broken but still used for checksums.
Minifier stub Tool that strips whitespace, renames variables, and shrinks source code for faster delivery.

OAuth 2.0 stub Authorization framework that issues access tokens on behalf of a user.
Open Graph stub Meta-tag protocol from Facebook that controls how URLs appear when shared.

Primary key stub Column (or set of columns) that uniquely identifies each row in a table.
PWA stub Progressive Web App , installable web app with service-worker-powered offline support.

Redis stub In-memory key-value store often used for caching, queues, and rate limiting.
Regex stub Regular Expression , pattern-matching mini-language for strings.
REST stub Representational State Transfer , API style using HTTP verbs on resource URLs.
robots.txt stub Root-level text file that tells crawlers which paths they may or may not index.

Service Worker stub Browser-side script that can intercept fetch requests , enables offline and push.
SHA-1 stub 160-bit Secure Hash Algorithm , deprecated for security but still used in legacy systems.
SHA-256 stub 256-bit hash from the SHA-2 family, the default modern checksum hash.
Source map stub File that maps compiled/minified code back to its original source for debugging.
SQL stub Structured Query Language , declarative language for relational databases.
SQLite stub Self-contained serverless SQL database stored in a single file.
sRGB stub Standard RGB , default color space of the web, ~72% of the visible gamut.
SSH key stub Public/private keypair used for passwordless SSH and Git authentication.
Structured data stub Schema.org markup (JSON-LD) that makes a page understandable to search engines.

_template *How to use this file.* Copy the block below the line into a new `{term-slug}.md` file in `data/glossary/`. Replace every `<…>` placeholder.
Throttle stub Wrap a function so it fires at most once per N ms regardless of how often it's called.
TLS stub Transport Layer Security , successor to SSL, the cryptographic layer under HTTPS.
TOML stub Tom's Obvious Minimal Language , readable config format used by Rust, Python packaging, etc.

Unicode stub Universal character set covering every script and emoji in one encoding standard.
Unix timestamp stub Integer seconds since 1970-01-01 00:00:00 UTC , the standard absolute time reference.
URL encoding stub Percent-encoding that makes unsafe characters transportable in URLs.
UTC stub Coordinated Universal Time , the global reference time zone, offset +00:00.
UTF-8 stub Variable-length Unicode encoding, backward compatible with ASCII.
UUID stub Universally Unique Identifier , 128-bit random or time-based ID, usually written as 8-4-4-4-12 hex.

WebGL stub WebGL , GPU-accelerated 3D graphics API for browsers, based on OpenGL ES.
Webhook stub HTTP callback the server fires at a caller-provided URL when an event occurs.
WebSocket stub Persistent bidirectional TCP connection over a single HTTP-upgraded socket.

XML stub Extensible Markup Language , verbose structured data format used for configs and legacy APIs.
XSS stub Cross-Site Scripting , attack that injects attacker-controlled JS into a victim's page.

YAML stub YAML Ain't Markup Language , human-readable data serialization, common in config files.