WebSockets enable two-way, persistent communication between client and server, making them ideal for real-time applications like chat apps, games, or live dashboards.

How WebSockets work:

• Client opens a WebSocket connection to the server.
• Once connected, data flows in both directions over a single TCP connection.
• Unlike HTTP, there’s no need to constantly poll the server for updates.

Use cases:

• Real-time chat or messaging apps.
• Multiplayer gaming.
• Collaborative document editing (like Google Docs).
• Stock market or IoT dashboards.

Basic example (Node.js + ws library):

jsКопироватьРедактироватьconst WebSocket = require('ws');
const server = new WebSocket.Server({ port: 8080 });

server.on('connection', socket => {
  socket.send('Welcome to the WebSocket server!');
  socket.on('message', msg => {
    console.log('Received:', msg);
  });
});

Frontend (JavaScript):

jsКопироватьРедактироватьconst ws = new WebSocket('ws://localhost:8080');
ws.onmessage = event => console.log(event.data);
ws.send('Hello server!');

WebSockets are low-latency and more efficient than long polling. They’re essential for developers building fast, responsive, real-time apps.