The Web platform: Browser technologies

Core platform
HTML
DOM
ECMAScript and JavaScript
URL
Fetch (includes CORS)
XMLHttpRequest
Encoding
CSS features
CSS roadmap
Animations
Background-image options
Border images
Border radius (rounded corners)
Box shadows
Box sizing
Cascading and inheritance
Colors
Compositing and Blending
Device Adaptation
Downloadable fonts (@font-face)
Exclusions
Feature queries (@supports)
Filter Effects
Fixed positioning (position:fixed)
Flexible box layout (Flexbox)
Font-feature settings
Font loading
Gradients
Grid layout
Hyphenation
Image Values and Replaced Content
Logical properties
Masking
Media Queries
Motion paths
Multiple-column layout
Multiple backgrounds
Opacity
Overflow
Pointer events
Pseudo-elements
Scroll Snap Points
Selectors
Shapes
Sticky positioning (position:sticky)
Style attributes
Syntax
Text decoration
Text overflow
Text shadows
Transforms (2D)
Transforms (3D)
Transitions
Values and Units
Will Change
Writing modes
CSSOM (CSS Object Model)
CSSOM View Module
Graphics and typography
Canvas
WebGL
SVG
WOFF
MathML
Web Animations
Media
Web Audio API
WebVTT
Media Source Extensions
Media Fragments
Platform interaction, events, messaging
Notifications API
Cross-document messaging
Channel messaging
Fullscreen API
Geofencing
Geolocation
Device Orientation
Screen Orientation
UI Events (formerly DOM Events)
Pointer Events
Touch Events
Pointer Lock
Gamepad
getUserMedia
Battery Status
Vibration
Beacon
HTML Media Capture (the capture attribute)
Clipboard API and events
Storage and Files
Storage (NavigatorStorage+StorageManager)
Web Storage (localStorage)
Indexed Database
File API
Blob URLs
File Reader
Real-time communication
WebRTC
Object RTC (ORTC) API for WebRTC
WebSocket protocol
WebSocket API
Server-Sent Events
Push API
Web Components
Custom Elements
Shadow DOM
Templates
HTML bonus features
classList (DOMTokenList)
dataset (data-* attributes)
async for scripts
defer for scripts
Session-history management
hashchange
Sandboxed iframe
Drag and drop
contentEditable
HTML Editing APIs
ARIA
Performance optimization and analysis
Web Workers
Shared Workers
Timing control for script-based animations
Navigation Timing
Page Visibility
User Timing
Performance Timeline
High Resolution Time
SIMD (Single instruction, multiple data)
Security and privacy
Content Security Policy (CSP)
Upgrade Insecure Requests
Web Cryptography API
Referrer policy
Tracking Preference Expression (DNT)
Other core-platform bonus features
Structured cloning
Transferable objects
Mutation observers
Streams
DOM Parsing and Serialization
DOM XPath
Quirks Mode
Internationalization API
Promises
JSON parsing
Typed Array
Service Workers
querySelector() method
matches() method
matchMedia() method
data URLs
Foundations
HTTP
HTTP/2
TLS
Cookies
Origin
Unicode
MIME Sniffing
Various other
Web IDL
Link header
Content-Disposition header
A feature history of the modern Web Platform

Legend

 
 
Can I use...
 
 
MDN (Mozilla Developer Network Reference)
 
 
Tests: associated test suite
 
 
HTML5 Please recommends as ready to use
 
 
HTML5 Please recommends using with caution