JavaScript, often abbreviated as JS, is a programming language that is one of the core technologies of the World Wide Web, alongside HTML and CSS. As of 2022, 98% of websites use JavaScript on the client side for webpage behavior, often incorporating third-party libraries. All major web browsers have a dedicated JavaScript engine to execute the code on users' devices.
ECMAScript is a JavaScript standard intended to ensure the interoperability of web pages across different web browsers. It is standardized by Ecma International in the document ECMA-262.
SpiderMonkey is open-source JavaScript and WebAssembly engine by the Mozilla Foundation.
Rhino is a JavaScript engine written fully in Java and managed by the Mozilla Foundation as open source software. It is separate from the SpiderMonkey engine, which is also developed by Mozilla, but written in C++ and used in Mozilla Firefox.
WURFL is a set of proprietary application programming interfaces (APIs) and an XML configuration file which contains information about device capabilities and features for a variety of mobile devices, focused on mobile device detection. Until version 2.2, WURFL was released under an "open source / public domain" license. Prior to version 2.2, device information was contributed by developers around the world and the WURFL was updated frequently, reflecting new wireless devices coming on the market. In June 2011, the founder of the WURFL project, Luca Passani, and Steve Kamerman, the author of Tera-WURFL, a popular PHP WURFL API, formed ScientiaMobile, Inc to provide commercial mobile device detection support and services using WURFL. As of August 30, 2011, the ScientiaMobile WURFL APIs are licensed under a dual-license model, using the AGPL license for non-commercial use and a proprietary commercial license. The current version of the WURFL database itself is no longer open source.
Tamarin is a discontinued free software virtual machine with just-in-time compilation (JIT) support intended to implement the 4th edition of the ECMAScript (ES4) language standard. Tamarin source code originates from ActionScript Virtual Machine 2 (AVM2) developed by Adobe Systems, as introduced within Adobe Flash Player 9, which implements ActionScript 3 scripting language. ActionScript Virtual Machine 2 was donated as open-source to Mozilla Foundation on November 7, 2006, to develop Tamarin as a high-performance virtual machine, with the support from broad Mozilla community, to be used by Mozilla and Adobe Systems in the next generation of their JavaScript and ActionScript engines with the ultimate aim to unify the scripting languages across web browsers and Adobe Flash platform and ease the development of better performing rich web applications.
TypeScript is a free and open-source high-level programming language developed by Microsoft that adds static typing with optional type annotations to JavaScript. It is designed for the development of large applications and transpiles to JavaScript. Because TypeScript is a superset of JavaScript, all JavaScript programs are syntactically valid TypeScript, but they can fail to type-check for safety reasons.
V8 is a free and open-source JavaScript and WebAssembly engine developed by the Chromium Project for Chromium and Google Chrome web browsers. The project's creator is Lars Bak. The first version of the V8 engine was released at the same time as the first version of Chrome: 2 September 2008. It has also been used on the server side, for example in Couchbase and Node.js.
JSLint is a static code analysis tool used in software development for checking if JavaScript source code complies with coding rules. It is provided primarily as a browser-based web application accessible through the domain jslint.com, but there are also command-line adaptations. It was created in 2002 by Douglas Crockford.
Node.js is a cross-platform, open-source server environment that can run on Windows, Linux, Unix, macOS, and more. Node.js is a back-end JavaScript runtime environment, runs on the V8 JavaScript Engine, and executes JavaScript code outside a web browser.
Chakra is a free and open-source JavaScript engine developed by Microsoft for its Microsoft Edge Legacy web browser. It is a fork of the same-named JScript engine used in Internet Explorer. Like the EdgeHTML browser engine, the declared intention was that it would reflect the "Living Web". The core components of Chakra were open-sourced as ChakraCore.
CommonJS is a project with the goal to establish conventions on the module ecosystem for JavaScript outside of the web browser. The primary reason for its creation was a major lack of commonly accepted forms of JavaScript module units which could be reusable in environments different from that provided by conventional web browsers running JavaScript scripts.
A browser speed test is a computer benchmark that scores the performance of a web browser, by measuring the browser's efficiency in completing a predefined list of tasks. In general the testing software is available online, located on a website, where different algorithms are loaded and performed in the browser client. Typical test tasks are rendering and animation, DOM transformations, string operations, mathematical calculations, sorting algorithms, graphic performance tests and memory instructions. Browser speed tests have been used during browser wars to prove superiority of specific web browsers. The popular Acid3 test is no particular speed test but checks browser conformity to web standards.
Cloud9 IDE is an Online IDE, published as open source from version 2.0, until version 3.0. It supports multiple programming languages, including C, C++, PHP, Ruby, Perl, Python, JavaScript with Node.js, and Go.
asm.js is a subset of JavaScript designed to allow computer software written in languages such as C to be run as web applications while maintaining performance characteristics considerably better than standard JavaScript, which is the typical language used for such applications.
This is a list of articles related to the JavaScript programming language.
ESLint is a static code analysis tool for identifying problematic patterns found in JavaScript code. It was created by Nicholas C. Zakas in 2013. Rules in ESLint are configurable, and customized rules can be defined and loaded. ESLint covers both code quality and coding style issues. ESLint supports current standards of ECMAScript, and experimental syntax from drafts for future standards. Code using JSX or TypeScript can also be processed when a plugin or transpiler is used.
Babel is a free and open-source JavaScript transcompiler that is mainly used to convert ECMAScript 2015+ (ES6+) code into backwards-compatible JavaScript code that can be run by older JavaScript engines. It allows web developers to take advantage of the newest features of the language.
Microsoft, a technology company historically known for its opposition to the open source software paradigm, turned to embrace the approach in the 2010s. From the 1970s through 2000s under CEOs Bill Gates and Steve Ballmer, Microsoft viewed the community creation and sharing of communal code, later to be known as free and open source software, as a threat to its business, and both executives spoke negatively against it. In the 2010s, as the industry turned towards cloud, embedded, and mobile computing—technologies powered by open source advances—CEO Satya Nadella led Microsoft towards open source adoption although Microsoft's traditional Windows business continued to grow throughout this period generating revenues of 26.8 billion in the third quarter of 2018, while Microsoft's Azure cloud revenues nearly doubled.
