JavaScript is the third part of the web development triangle — HTML, CSS, and JavaScript. It is a dynamic multi-paradigm programming language that is natively supported by all web browsers. It is used to add dynamic capabilities to web pages and to control the behavior of its elements.

The JavaScript language is an implementation of its standard, ECMAScript. Almost every browser has its own implementation of the ECMAScript standard. For example, Chrome has V8, Safari has WebKit, and Edge has Chakra.

JavaScript is the basis of all web application development frameworks, such as Angular, React, and others. Additionally, apart from frontend development, it has been adapted for backend development via the Node.js runtime environment.

The ES2015 version brought major enhancements to the language with new syntax for classes and modules, the for-of loop, arrow functions, and more. The latest version, ES2017, introduced the anticipated async/await feature.