title: What is hashCode used for? Is it unique?
body: <p>I notice there is a <code>getHashCode()</code> method in every controls, items, in WP7, which return a sequence of number. Can I use this hashcode to identify an item? For example I want to identify a picture or a song in the device, and check it whereabout. This could be done if the hashcode given for specific items is unique.</p>
  
  <p>Can you help explain to me what is hashCode and <code>getHashCode()</code> use for?</p>