Streams Standard
Streams are how modern browsers handle large data: fetch response bodies, file reads, compression, and encoding are all stream-based. Understanding backpressure and piping is essential for efficient data processing.
What It Defines
Defines ReadableStream, WritableStream, and TransformStream — the browser's primitive for processing data incrementally. Enables backpressure, piping, teeing, and composable stream transforms. Used by Fetch (response.body), File API, Compression Streams, and Web Codecs.
Canonical (Normative)
Convenient (Practical)
Maintains the living standards for the web platform: HTML, DOM, Fetch, URL, Streams, and more. These are continuously updated living documents, not versioned snapshots.
Related Specs
Every fetch() call and XHR request is governed by this spec. It also defines CORS behavior in detail.
Required whenever you work with binary data in JavaScript — ArrayBuffers from fetch, WebSocket binary frames, file contents, or crypto operations all need encoding/decoding. UTF-8 is the web's canonical encoding.
Service Workers power offline support, background sync, and push notifications. Required for serious PWA/installable app behavior.