W3C Technical Reports
W3C
CSS, CSP, WebAuthn (with FIDO), SVG, and accessibility specs are W3C Recommendations even when WHATWG owns HTML.
What It Is
W3C publishes Recommendations (web standards), Candidate Recommendations, Notes, and Registries. CSS, accessibility, security policies, Service Workers, WebGPU, and many browser APIs.
Taxonomy
By status (Rec, CR, WD, Note, Registry) · By tag (CSS, Security, Media, Accessibility…)
Top-Level Categories
Master Catalog
Sub-Indexes & Guides
Publishes web platform specs including CSS, accessibility, security policies, Service Workers, Web App Manifest, and many browser APIs. Also maintains some versioned HTML/DOM specs.
View all bodies →Curated specs from W3C
A well-configured CSP is the strongest mitigation against XSS. Required by modern security audits and browser hardening.
PNG is the default lossless image format on the web — screenshots, UI assets, icons with transparency, and OCR-friendly graphics. Chunk structure matters for metadata stripping and security review.
GIF remains common for short animated loops and legacy assets. GIF89a extension blocks enable animation timing and transparent pixels.
SVG powers icons, logos, charts, and interactive graphics. Because it's XML (not opaque binary), XSS and SSRF via embedded references are real risks in upload pipelines.
WOFF2 is the standard delivery format for `@font-face` on the web — smaller than raw TTF/OTF. Font table structure comes from OpenType; WOFF2 is the transport envelope.
Legacy Windows bitmap format still encountered in scanners, game assets, and older pipelines. Simple header + raw pixels — useful for understanding uncompressed raster layout.
Favicons (`favicon.ico`) and Windows app icons use this format. Modern favicons often use PNG inside ICO containers or switch to `<link rel="icon">` with PNG/SVG.
FLAC is the standard lossless audio format for archival and audiophile distribution. Metadata block chain is a clean example of typed extensible headers.
+47 more in specs browser