title: RequireJS - When specify module id in define()
body: <p>In RequireJS documents (<a href="http://requirejs.org/docs/api.html#modulename" rel="nofollow">http://requirejs.org/docs/api.html#modulename</a>), I couldn't understand this sentence.</p>
  
  <blockquote>
    <p>You can explicitly name modules yourself, but it makes the modules less portable</p>
  </blockquote>
  
  <p>My question is</p>
  
  <ol>
  <li>Why explicitly naming module makes less portable?</li>
  <li>When explicitly naming module needed?</li>
  </ol>