title: Cannot run node.js example. module.js:340 throw err cannot find module
body: <p>When I type in node example.js to my command prompt it gives me an error message. </p>
  
  <p>This is the code I'm using.</p>
  
  <pre><code>var http = require('http');
  http.createServer(function (req, res) {
  res.writeHead(200, {'Content-Type': 'text/plain'});
  res.end('Hello World\n');
  }).listen(1337, 'localhost');
  console.log('Server running at http://localhost:1337/');
  </code></pre>
  
  <p>I got that directly from the node.js website and it worked last night. It won't work today. Some help would be appreciated please.</p>