title: What is root reference?
body: <pre><code>class GCTest {
       static Object r1; 
  
       static void Main() {
           r1 = new Object();
           Object r2 = new Object();
           Object r3 = new Object();
           System.GC.Collect(); // what can be reclaimed here ?
  
           r1 = null;
           r3.ToString();
           System.GC.Collect(); // what can be reclaimed here ?
       }
      }
  </code></pre>
  
  <p>// code from - DonBox's Essential .Net</p>