Node.js is a JavaScript runtime that allows developers to run JavaScript outside of the browser. It is built on the V8 engine and provides APIs for filesystem access, networking, and process control. Node.js is widely used for building backend services, APIs, command line tools, and real time applications. Its event driven, non blocking architecture is well suited for handling large numbers of concurrent requests. Node.js enables full stack JavaScript development, reducing context switching between frontend and backend code.
how it works
Node.js uses an event loop to manage asynchronous operations without blocking the main thread. Calls such as file reads or network requests are delegated to the system, and Node.js processes results when they complete. Packages are managed through npm, which provides access to thousands of community libraries. Node.js services often run on servers or inside containers. Because it is single threaded by default, high CPU workloads may require worker threads or separate processes.