Node.js is a powerful and popular open-source JavaScript runtime built on the V8 JavaScript engine. It allows developers to execute JavaScript code server-side, outside the context of a web browser. Node.js has gained widespread adoption for its non-blocking, event-driven architecture, making it well-suited for building scalable and high-performance network applications. Node.js is a versatile and efficient runtime that has revolutionized server-side development with its non-blocking, event-driven architecture. It is widely adopted for building scalable and performant web applications, APIs, and real-time applications, making it a valuable tool in modern development stacks.