title: The difference between unsigned long and UINT64
body: <p>What is the difference between <code>unsigned long</code> and <code>UINT64</code>?
  I think they are the same, but I'm not sure.
  The definition of <code>UINT64</code> is :</p>
  
  <pre><code>typedef unsigned __int64    UINT64
  </code></pre>
  
  <p>(by using StdAfx.h)</p>