title: Empty <title> element in HTML stops HTML from loading if written as <title />
body: <p>Probably a really dumb question - but in an HTML document, why does the following:</p>
  
  <pre><code> &lt;title&gt;&lt;/title&gt;
  </code></pre>
  
  <p>work ok (according to <a href="http://www.w3schools.com/tags/tryit.asp?filename=tryhtml_basic" rel="nofollow">http://www.w3schools.com/tags/tryit.asp?filename=tryhtml_basic</a>)</p>
  
  <p>but then </p>
  
  <pre><code>&lt;title /&gt;
  </code></pre>
  
  <p>will stop the HTML from rendering?</p>
  
  <p>Thanks</p>