What is WebSocket and what is it used for?

WebSocket is a communication protocol that provides a bidirectional, persistent communication channel between the client and server over a single TCP connection. Unlike traditional HTTP, where the client sends a request and receives a response, WebSocket allows the server to send data to the client at any time without a prior request.

This is useful for applications where real-time data transfer is important, such as in chat applications, online games, trading platforms, notification systems, and other interactive services.