Node.jsA JavaScript runtime built on V8 — event-driven I/O for servers, CLIs, and tooling. runs JavaScript outside the browser for APIs, CLIs, and real-time servers. Its non-blocking I/O model powers npmNode Package Manager — the default registry and CLI for installing JavaScript and TypeScript libraries.'s ecosystem — Express, NestJS, webpack, and millions of packages. Example: a chat server handling thousands of WebSocket connections on one thread via callbacks and later async/await.

NodeNode.js — JavaScript on the server via an event-driven runtime built on V8. made JavaScript a full-stack language and reshaped how teams build web backends.

V8Google's open-source JavaScript engine — powers Chrome, Node.js, and many embedded runtimes. plus an event loop proved JS could handle I/O-bound servers at scale, not just browser UIUser interface — the parts of software people see and interact with..