title: What do two left angle brackets mean?
body: <p>I saw a loop which I've never seen before:</p>
  
  <pre><code>for (int i = 0; i &lt; (1 &lt;&lt; list.Count); i++)
  </code></pre>
  
  <p>I can't understand what <code>(1 &lt;&lt; list.Count)</code> means, maybe someone could explain me this?</p>