Node.js is a powerful, open-source, server-side JavaScript runtime environment built on Chrome's V8 JavaScript engine. It allows developers to write server-side applications in JavaScript, traditionally a client-side scripting language. Node.js is renowned for its event-driven, non-blocking I/O model, which makes it highly efficient and scalable for building real-time web applications, APIs, and microservices. Its package manager, npm, hosts over a million reusable packages, providing developers with a vast ecosystem of tools and libraries to streamline development processes. Node.js is particularly well-suited for handling I/O-heavy tasks and asynchronous operations, making it a preferred choice for high-performance and data-intensive applications. With its thriving community and active development, Node.js continues to push the boundaries of server-side JavaScript development, enabling developers to build fast, scalable, and feature-rich applications across various domains.