title: Using the link tag instead of the meta tag in semantic markup when the value is a URL
body: <p>I was looking at YouTube's HTML source code for video pages and saw these tags:</p>
  
  <pre><code>&lt;div id="watch7-container" itemscope itemtype="http://schema.org/VideoObject"&gt;
    &lt;link itemprop="url" href="http://www.youtube.com/watch?v=ikbEBp5BeCM"&gt;
    &lt;meta itemprop="name" content="THE TEST"&gt;
    &lt;meta itemprop="duration" content="PT1M10S"&gt;
    &lt;meta itemprop="unlisted" content="False"&gt;
    &lt;link itemprop="embedURL" href="http://www.youtube.com/v/ikbEBp5BeCM?autohide=1&amp;amp;version=3"&gt;
    &lt;meta itemprop="playerType" content="Flash"&gt;
    &lt;meta itemprop="width" content="640"&gt;
    &lt;meta itemprop="height" content="480"&gt;
  </code></pre>
  
  <p>Every time the value is a URL, YouTube uses the <code>link</code> tag instead of the <code>meta</code> tag. </p>
  
  <p><a href="http://validator.w3.org/" rel="noreferrer">http://validator.w3.org/</a> validated both <code>&lt;meta content="http://..." itemprop="url"&gt;</code> and <code>&lt;link href="http://..." itemprop="url"&gt;</code> as being valid HTML.</p>
  
  <p>What is the benefit of doing this?</p>