chat.js

nc localhost 8000  (open in several sessions)

tcp-server.js

 var net = require('net');

 var server = net.createServer(function(socket) {
     socket.write('hello\n');
     socket.end('world\n');
  });

 server.listen(8000);

telnet localhost 8000
nc localhost 8000
hello
world

web-server.js

var http = require('http');

http.createServer(function (req, res) {
  res.writeHead(200, {'Content-Type': 'text/plain'});
  res.end('Hello World\n');
}).listen(3000, '127.0.0.1');

console.log('Server running at http://127.0.0.1:3000/');

curl http://localhost:3000
Hello World