Glossary

This page defines technical terms and abbreviations used across the site.

Video and subtitles

  • MKV — Matroska Video, a free and open container format that can hold video, audio, and subtitle streams in a single file.
  • MP4 — MPEG-4 Part 14, a common multimedia container format (.mp4).
  • SRT — SubRip Subtitle, a plain-text subtitle format (.srt).
  • VobSub — a subtitle format that stores subtitles as images (a .sub file with a .idx index file).
  • TTML — Timed Text Markup Language, an XML-based subtitle format.
  • ASS — Advanced SubStation Alpha, a text subtitle format supporting styling and positioning.
  • VTT — Web Video Text Tracks, a text subtitle/caption format used on the web.
  • LRC — a simple lyric/subtitle format where each line carries a timestamp.
  • VLC — a free, open-source media player.
  • ffmpeg — a command-line tool for recording, converting, and streaming audio and video.

Security and networking

  • OpenSSL — a toolkit implementing the SSL and TLS protocols, used to create and manage certificates and connections.
  • SSL — Secure Sockets Layer, an older protocol for encrypting network traffic.
  • TLS — Transport Layer Security, the successor to SSL.
  • VPN — Virtual Private Network, a service that routes your traffic through an encrypted tunnel.
  • CDN — Content Delivery Network, a network of servers that cache content close to users to speed up delivery.
  • OCR — Optical Character Recognition, converting images of text into machine-readable text.
  • EDR — Endpoint Detection and Response, security software that watches endpoints for malicious behaviour and supports incident response.
  • CSP — Content Security Policy, a browser standard that restricts which resources a page can load.
  • VirusTotal — a free service that scans files and URLs against many antivirus engines.
  • CRX — the packaged file format used for Chrome extensions.
  • CSR — Certificate Signing Request, a block of text sent to a certificate authority when requesting a certificate.
  • SAN — Subject Alternative Name, a certificate field listing the domains and hosts it’s valid for.
  • PEM — Privacy-Enhanced Mail, a base64-encoded (text) format for certificates and keys.
  • DER — Distinguished Encoding Rules, a binary format for certificates.
  • PKCS#12 — a file format (.pfx/.p12) that bundles a certificate together with its private key.
  • RSA — a widely used public-key cryptosystem for encryption and signatures.
  • bcrypt — a deliberately slow password-hashing function designed to resist brute-force attacks.
  • PBKDF2 — Password-Based Key Derivation Function 2, used to derive cryptographic keys from passwords.
  • NIST — National Institute of Standards and Technology, a US standards body that publishes security guidance.

Accessibility

  • WCAG — Web Content Accessibility Guidelines, the W3C standard for making web content accessible to people with disabilities.
  • DDA — Disability Discrimination Act 1992, Australian legislation that makes it unlawful to discriminate on the grounds of disability.

Web and markup

  • HTML — HyperText Markup Language, the standard language for structuring web pages.
  • CSS — Cascading Style Sheets, used to style the presentation of web pages.
  • JavaScript — the scripting language that adds interactivity to web pages (often abbreviated as JS).
  • YAML — “YAML Ain’t Markup Language”, a human-readable data format used for configuration and post front matter.
  • Markdown — a lightweight markup language for formatting plain text.
  • GFM — GitHub-Flavoured Markdown, the Markdown variant used on GitHub and by this site.
  • URL — Uniform Resource Locator, the address of a resource on the web.

Email and authentication

  • DMARC — Domain-based Message Authentication, Reporting & Conformance, a protocol that uses SPF and DKIM to authenticate e-mail.
  • SPF — Sender Policy Framework, a DNS TXT record listing which servers may send e-mail for a domain.
  • DKIM — DomainKeys Identified Mail, a way of signing e-mail so receivers can verify it hasn’t been tampered with.
  • MBOX — a plain-text format that stores a mailbox (used by Gmail exports).
  • PST — Personal Storage Table, the mailbox file format used by Outlook.
  • MFA — Multi-Factor Authentication, requiring more than one proof of identity to sign in.
  • Passkey — a passwordless, FIDO-based credential stored on a device or in a password manager.
  • OTP — One-Time Password, a short-lived code used as a second factor.
  • TOTP — Time-based One-Time Password, an OTP generated from a shared secret and the current time.
  • Thunderbird — Mozilla’s free, open-source e-mail client.

Software and platforms

  • SDK — Software Development Kit, a set of tools for building software for a platform.
  • NDK — Native Development Kit, Android’s toolset for building native (C/C++) code.
  • JDK — Java Development Kit, the toolset used to compile and run Java programs.
  • APK — Android Package, the installable package format for Android apps.
  • WebAssembly (WASM) — a low-level binary format that runs in browsers and other runtimes.
  • Emscripten — a toolchain that compiles C/C++ into WebAssembly.
  • Kubernetes — an open-source platform for automating the deployment and scaling of containerised applications.
  • GAM — Google Apps Manager, a command-line tool for managing Google Workspace.
  • Google Workspace — Google’s suite of business productivity tools (formerly G Suite).

General

  • BBC — British Broadcasting Corporation, the UK public broadcaster behind BBC iPlayer.
  • Tesseract — an open-source OCR engine.
  • README — a file that describes a project and its usage.

Definitions may be added or expanded as new posts are published.