title: Default using directives in new C# files
body: <p>Why does Visual Studio 2008 automatically insert the following <em>using directives</em> into each new C# file I create?</p>
  
  <pre><code>using System; 
  using System.Collections.Generic; 
  using System.Text;
  </code></pre>
  
  <p>What's so special about these namespaces? Are these the most frequently used ones?</p>