Check out example codes for "socket io script". It will help you in understanding the concepts better.

Code Example 1

const socket = new WebSocket('ws://localhost:3000');socket.onopen(() => {  socket.send('Hello!');});socket.onmessage(data => {  console.log(data);});

Code Example 2

<script src="/socket.io/socket.io.js"></script>
<script>
  const socket = io();
</script>

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