Node.js is a cross-platform runtime environment and library for running JavaScript applications outside the browser. It is used for creating server-side and networking web applications. It is open source and free to use. It
Many of the basic modules of Node.js are written in JavaScript. Node.js is mostly used to run real-time server applications.
The definition given by its official documentation is as follows:
Node.js is a platform built on Chrome's JavaScript runtime for easily building fast and scalable network applications. Node.js uses an event-driven, non-blocking I/O model that makes it lightweight and efficient, perfect for data-intensive real-time applications that run across distributed devices.?
Node.js also provides a rich library of various JavaScript modules to simplify the development of web applications.