title: Why do primitive data types work without including the System namespace?
body: <p>I read that all primitives fall under the <code>System</code> namespace.  If I comment out <code>using System</code> I would expect there to be a build error in my program,   however it is running successfully.  Why is this?</p>
  <p><a href="https://i.stack.imgur.com/oTkly.png" rel="nofollow noreferrer"><img src="https://i.stack.imgur.com/oTkly.png" alt="Attached the snap of my sample program." /></a></p>