title: In HTML what happens with the content of unrecognised Tags?
body: <p>There is this <a href="http://msdn.microsoft.com/en-us/library/ms537512%28v=vs.85%29.aspx#dlrevealed" rel="nofollow">quote</a> from Microsoft:</p>
  
  <pre><code>&lt;![if lt IE 8]&gt;
  &lt;p&gt;Please upgrade to Internet Explorer version 8.&lt;/p&gt;
  &lt;![endif]&gt;
  </code></pre>
  
  <blockquote>
    <p>When comparing this type of comment to
    the basic HTML Comment, notice that
    there are no hyphens ("--")
    immediately after the opening "" of
    the comment block; therefore, the
    comment delimiters are treated as
    unrecognized HTML. Because the browser
    does not recognize the
    downlevel-revealed conditional
    comment, it does nothing with it.</p>
  </blockquote>
  
  <p>And there is the commonly known HTML5-Video Fallback solution.</p>
  
  <pre><code>&lt;video ...&gt;  
      &lt;!-- If the browser doesn't understand the &lt;video&gt; element,  reference a Flash file.--&gt;  
      &lt;embed ...&gt;&lt;/embed&gt;  
  &lt;/video&gt;
  </code></pre>
  
  <ul>
  <li><p>So what is happening witht he contents of an recognised Tag?</p></li>
  <li><p>Is this standardized somehow or just up to the browser how to implement?</p></li>
  </ul>