Node JS is a packaged compilation of Google’s V8 JavaScript engine, the libuv platform abstraction layer, and a core library, which is itself primarily written in JavaScript. Node JS shines in real-time web applications employing push technology over web sockets. The main principle of Node JS: use non-blocking, event-driven I/O to remain lightweight and efficient in the face of data-intensive real-time applications that run across distributed devices. It replaces the traditional request-response paradigm with a fast, two-way communication model. It is asynchronous without the use of threads; it is not memory-intensive. Node JS web sockets run on TCP, not HTTP, so low-overhead client-server communication kept enabled in both the directions.