How the bit.ly system get the path from url?
<blockquote>
  <p><strong>Possible Duplicate:</strong><br>
  <a href="http://stackoverflow.com/questions/3901635/php-passing-parameters-via-url">PHP passing parameters via URL</a>  </p>
</blockquote>



<p>I know that if you have a page <code>www.domain.com/?id=ABC</code> you can get the <em>ABC</em> in the <code>index.php</code> file using a </p>

<p><code>$_GET['id'];</code></p>

<p>My question is how does a <code>bit.ly/ABC</code> can give the <em>ABC</em> to their php file without having an <code>?id=ABC</code> in the path?</p>
