What is Node.js? What is it used for?

Node.js is a run-time JavaScript environment built on top of Chrome’s V8 engine. It uses an event-driven, non-blocking I/O model. It is lightweight and so efficient. Node.js has a package ecosystem called npm.

Node.js can be used to build different types of applications such as web application, real-time chat application, REST API server etc. However, it is mainly used to build network programs like web servers

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