gistfile1.js

// SERVER HERE
var http = require('http'),  
    io = require('socket.io'), // for npm, otherwise use require('./path/to/socket.io') 

server = http.createServer(function(req, res){ 
 // your normal server code 
 res.writeHead(200, {'Content-Type': 'text/html'}); 
 res.end('<h1>Hello world</h1>'); 
});
server.listen(80);
  
// socket.io 
var socket = io.listen(server); 
socket.on('connection', function(client){ 
  // new client is here! 
  client.on('message', function(){ … }) 
  client.on('disconnect', function(){ … }) 
});

// CLIENT HERE
var socket = new io.Socket({node_server_url}); 
socket.connect();
socket.on('connect', function(){ … }) 
socket.on('message', function(){ … }) 
socket.on('disconnect', function(){ … })