title: Difference between @android:id/list and @id/list
body: <p>what is the difference between </p>
  
  <pre><code>@android:id/hello
  </code></pre>
  
  <p>and</p>
  
  <pre><code>@id/hello
  </code></pre>
  
  <p>I ask this, cause apparently we MUST use @android:id/list in the Class when we want to extend ListActivity.</p>