title: <out T> vs <T> in Generics
body: <p>What is the difference between <code>&lt;out T&gt;</code> and <code>&lt;T&gt;</code>? For example:</p>
  
  <pre><code>public interface IExample&lt;out T&gt;
  {
      ...
  }
  </code></pre>
  
  <p>vs.</p>
  
  <pre><code>public interface IExample&lt;T&gt;
  {
      ...
  }
  </code></pre>