JavaScript (JS) is a lightweight, interpreted or JIT compiled programming language with first-class functions. Most well-known as the scripting language for Web pages, many non-browser environments also use it, such as node.js and Apache CouchDB. JS is a prototype-based, multi-paradigm, dynamic scripting language, supporting object-oriented, imperative, and declarative (e.g. functional programming) styles. Read more about JavaScript.
This section of the site is dedicated to the JavaScript language itself, and not the parts that are specific to Web pages or other host environments. For information about APIs specific to Web pages, please see Web APIs and DOM.
Helpful tools for writing and debugging your JavaScript code.
Scratchpad, Web Console, JavaScript Profiler, Debugger, and more
Edit, debug, and monitor CSS, HTML, and JavaScript live in any web page
A JavaScript shell allows you to quickly test snippets of JavaScript code