title: What is the difference between require('mypackage.js') and require('mypackage')?
body: <p>Both these <code>require</code> statements appear to work the same way:</p>
  
  <p><code>var Mypackage = require('mypackage.js');</code></p>
  
  <p><code>var Mypackage require('mypackage');</code></p>
  
  <p>Is there a difference between them?</p>