title: C# generic function question
body: <p>How to understand the following code? What does "this" mean in the generic function prototype? Thanks!</p>
  
  <pre><code>public static class MyExtensions
  {
      public static MyStream&lt;T&gt; MySingle&lt;T&gt;(this T source)
      {
          return new MyStream&lt;T&gt;(source);
      }
  }
  </code></pre>