title: How do I prevent an image from showing up as a thumbnail option when my site is shared on Facebook?
body: <p>When a user shares my site on Facebook, Facebook allows them to select a thumbnail image to go along with the share.  I'd like the only image made available to be my site logo, but I'm not sure what the best way to accomplish this is.</p>
  
  <p>So for example, this should show up as an option:</p>
  
  <pre><code>&lt;img src="logo.png" /&gt;
  </code></pre>
  
  <p>But I'd like other images to be ignored:</p>
  
  <pre><code>&lt;img src="news1.jpg" /&gt;
  &lt;img src="news2.jpg" /&gt;
  &lt;img src="footerDetail.jpg" /&gt;
  </code></pre>