git clone git://github.com/Marak/hellonode.git
 cd hellonode
 node server.js

// requires node's http module
var http = require('http');

// creates a new httpServer instance
http.createServer(function (req, res) {
  
  // ^^ this is the callback, or request handler for the httpServer
  
  // respond to the browser, write some headers so the 
  // browser knows what type of content we are sending
  res.writeHead(200, {'Content-Type': 'text/plain'});
  
  // write some content to the browser that your user will see
  res.write('hello, i know nodejitsu.')
  
  // close the response
  res.end();
  
}).listen(80); // the server will listen on port 80