title: In Swift (iOS app), when do I need to use other integer types?
body: <p>I saw there are many integer types in Swift other than <code>Int</code>, for example:</p>
  
  <pre><code>Int8
  UInt32
  uint_fast16_t
  </code></pre>
  
  <p>I can understand their definitions but I am wondering when/why I should use them instead of <code>Int</code>?</p>
  
  <p>For example, <code>Int8</code> is a 8-bit integer. From my understanding, unless I want to save some memory, why bother using it?</p>
  
  <p>PS. I am using Swift for iOS app development. </p>