ECMAScript Language Specification
JavaScript is the execution model of the web. The spec is the canonical reference for language semantics — closures, coercion, prototype lookup, module resolution, and async scheduling.
What It Defines
The language specification for JavaScript. Defines syntax, types, the prototype chain, closures, iterators, generators, async/await, modules, Proxy/Reflect, WeakRef, and the memory model. Updated annually by TC39.
Canonical (Normative)
Convenient (Practical)
Related References
Publishes the ECMAScript (JavaScript) language specification and related standards. TC39 is the committee responsible for ECMAScript evolution.
Related Specs
The spec behind every HTML page, form, and browser API. The canonical reference for how browsers actually parse and process HTML.
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