Original author(s) | Sebastian McKenzie |
---|---|
Developer(s) | Contributors |
Initial release | September 28, 2014 [1] |
Stable release | 7.23.8 / January 8, 2024 [2] |
Repository | |
Written in | JavaScript |
Operating system | Linux, macOS, Solaris, FreeBSD, OpenBSD, AIX, Microsoft Windows |
Type | Compiler |
License | MIT [3] |
Website | babeljs |
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. [4]
Developers can use new JavaScript language features by using Babel to convert their source code into versions of JavaScript that a Web browser can process. [5] Babel can also be used to compile TypeScript into JavaScript. [6] The core version of Babel was downloaded 5 million times a month in 2016, and this increased to 16 million times a week in 2019. [7] [8]
Babel plugins transform syntax that is not widely supported into a backward-compatible version. For example, arrow functions, which are specified in ES6, are converted into regular function declarations. [9] Non-standard JavaScript syntax such as JSX can also be transformed. [10] [11]
Babel can automatically inject polyfills provided by core-js [12] for support features that are missing entirely from JavaScript environments. For example, static methods such as Array.from
and built-ins such as Promise
are available only in ES6 and above, but they can be used in older environments if core-js is used.
JavaScript, often abbreviated as JS, is a programming language and core technology of the World Wide Web, alongside HTML and CSS. As of 2023, 98.7% 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 standard for scripting languages, including JavaScript, JScript, and ActionScript. It is best known as 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.
jQuery is a JavaScript library designed to simplify HTML DOM tree traversal and manipulation, as well as event handling, CSS animations, and Ajax. It is free, open-source software using the permissive MIT License. As of August 2022, jQuery is used by 77% of the 10 million most popular websites. Web analysis indicates that it is the most widely deployed JavaScript library by a large margin, having at least three to four times more usage than any other JavaScript library.
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.
JSDoc is a markup language used to annotate JavaScript source code files. Using comments containing JSDoc, programmers can add documentation describing the application programming interface of the code they're creating. This is then processed, by various tools, to produce documentation in accessible formats like HTML and Rich Text Format. The JSDoc specification is released under CC BY-SA 3.0, while its companion documentation generator and parser library is free software under the Apache License 2.0.
Svelte is a free and open-source front-end component framework and language created by Rich Harris and maintained by the Svelte core team members. Svelte is not a monolithic JavaScript library imported by applications: instead, Svelte compiles HTML templates to specialized code that manipulates the DOM directly, which may reduce the size of transferred files and give better client performance. Application code is also processed by the compiler, inserting calls to automatically recompute data and re-render UI elements when the data they depend on is modified. This also avoids the overhead associated with runtime intermediate representations, such as virtual DOM, unlike traditional frameworks which carry out the bulk of their work at runtime, i.e. in the browser.
Google Closure Tools is a set of tools to help developers build rich web applications with JavaScript. It was developed by Google for use in their web applications such as Gmail, Google Docs and Google Maps. As of 2023, the project had over 230K LOCs not counting the embedded Mozilla Rhino compiler.
Node.js is a cross-platform, open-source JavaScript runtime environment that can run on Windows, Linux, Unix, macOS, and more. Node.js runs on the V8 JavaScript engine, and executes JavaScript code outside a web browser.
CommonJS is a project to standardize the module ecosystem for JavaScript outside of web browsers.
CoffeeScript is a programming language that compiles to JavaScript. It adds syntactic sugar inspired by Ruby, Python, and Haskell in an effort to enhance JavaScript's brevity and readability. Specific additional features include list comprehension and destructuring assignment.
Dart is a programming language designed by Lars Bak and Kasper Lund and developed by Google. It can be used to develop web and mobile apps as well as server and desktop applications.
In software development, a polyfill is code that implements a feature of the development environment that does not natively support the feature. Most often, it refers to a JavaScript library that implements an HTML5 or CSS web standard, either an established standard on older browsers, or a proposed standard on existing browsers. Polyfills are also used in PHP and Python. Formally, "a polyfill is a shim for a browser API."
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.
Ember.js is an open-source JavaScript web framework that utilizes a component-service pattern. It allows developers to create scalable single-page web applications by incorporating common idioms, best practices, and patterns from other single-page-app ecosystem patterns into the framework.
React is a free and open-source front-end JavaScript library for building user interfaces based on components. It is maintained by Meta and a community of individual developers and companies.
WebAssembly defines a portable binary-code format and a corresponding text format for executable programs as well as software interfaces for facilitating interactions between such programs and their host environment.
JSX formally is a JavaScript extension that allows creation of DOM trees using an XML-like syntax. Initially created by Facebook for use with React, JSX has been adopted by multiple web frameworks. Being a syntactic sugar, JSX is generally transpiled into nested JavaScript function calls structurally similar to the original JSX.
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.
Deno is a runtime for JavaScript, TypeScript, and WebAssembly that is based on the V8 JavaScript engine and the Rust programming language. Deno was co-created by Ryan Dahl, who also created Node.js.