UI Events
The foundational event model that every web application uses. Understanding event propagation (capture, target, bubble), event.preventDefault(), and the difference between key and code prevents input handling bugs.
What It Defines
Defines the DOM event types for user interaction: MouseEvent (click, dblclick, mousedown/up/move/over/out/enter/leave), KeyboardEvent (keydown, keyup, key, code), FocusEvent (focus, blur, focusin/out), InputEvent (beforeinput, input with inputType), WheelEvent, and CompositionEvent for IME input.
Canonical (Normative)
Convenient (Practical)
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.
Related Specs
Every frontend framework (React, Vue, Svelte) ultimately produces DOM operations. Understanding the event model and tree structure prevents subtle bugs.
The modern way to handle all pointing devices with one code path. Replaces separate mouse + touch event handling. Required for drawing apps, drag interactions, and multi-touch. Pressure and tilt enable pen/stylus features.
The spec behind every HTML page, form, and browser API. The canonical reference for how browsers actually parse and process HTML.