Javascript

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A scripting language used to create and control the content on a website, allowing you to program the behavior of web pages to do a specified action.

Javascript (Wikipedia)

JavaScript
Paradigmevent-driven, functional, imperative
Designed byBrendan Eich initially, plus other key contributors to the ECMAScript specification
First appearedDecember 4, 1995; 25 years ago (1995-12-04)
Stable release
ECMAScript 2020 / June 2020; 7 months ago (2020-06)
Preview release
ECMAScript 2021
Typing disciplineDynamic, duck
Filename extensions
  • .js
  • .cjs
  • .mjs
Major implementations
V8, JavaScriptCore, SpiderMonkey, Chakra
Influenced by
AWK,C, HyperTalk, Java,Lua, Perl, Python, Scheme, Self
Influenced
ActionScript, AtScript, CoffeeScript, Dart, JScript .NET, LiveScript, Objective-J, Opa, QML, Raku, TypeScript

JavaScript (/ˈɑːvəˌskrɪpt/), often abbreviated as JS, is a programming language that conforms to the ECMAScript specification. JavaScript is high-level, often just-in-time compiled, and multi-paradigm. It has curly-bracket syntax, dynamic typing, prototype-based object-orientation, and first-class functions.

Alongside HTML and CSS, JavaScript is one of the core technologies of the World Wide Web. JavaScript enables interactive web pages and is an essential part of web applications. The vast majority of websites use it for client-side page behavior, and all major web browsers have a dedicated JavaScript engine to execute it.

As a multi-paradigm language, JavaScript supports event-driven, functional, and imperative programming styles. It has application programming interfaces (APIs) for working with text, dates, regular expressions, standard data structures, and the Document Object Model (DOM). However, ECMAScript itself does not include any input/output (I/O), such as networking, storage, or graphics facilities, as the host environment (usually a web browser) provides those APIs.

JavaScript engines were originally used only in web browsers, but they are now embedded in some servers, usually via Node.js. They are also embedded in a variety of applications created with frameworks such as Electron and Cordova.

Although there are similarities between JavaScript and Java, including language name, syntax, and respective standard libraries, the two languages are distinct and differ greatly in design.

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