title: What is the right xmlns used for Facebook
body: <p>The Facebook documentation on this is inconsistent and confusing.</p>
  
  <p>I. Here: <a href="https://developers.facebook.com/docs/reference/plugins/like/" rel="nofollow">https://developers.facebook.com/docs/reference/plugins/like/</a></p>
  
  <p>It says: </p>
  
  <pre><code>&lt;html xmlns:fb="http://ogp.me/ns/fb#"&gt;
  </code></pre>
  
  <p>(if you fill in the form and click the get code button and then click the xfbml tag.)</p>
  
  <p>II. On this page: <a href="https://developers.facebook.com/docs/technical-guides/opengraph/opengraph-tutorial/#plugins" rel="nofollow">https://developers.facebook.com/docs/technical-guides/opengraph/opengraph-tutorial/#plugins</a></p>
  
  <p>It says:</p>
  
  <pre><code>xmlns:fb="https://www.facebook.com/2008/fbml"
  </code></pre>
  
  <p>Now the two urls above resolve to the same url: <a href="http://graph.facebook.com/schema/og/" rel="nofollow">http://graph.facebook.com/schema/og/</a></p>
  
  <p>III. But then we have: <a href="https://developers.facebook.com/docs/opengraphprotocol/" rel="nofollow">https://developers.facebook.com/docs/opengraphprotocol/</a></p>
  
  <pre><code>xmlns:og="http://ogp.me/ns#"
        xmlns:fb="https://www.facebook.com/2008/fbml"
  </code></pre>
  
  <p>Now the first url here does not even resolve to a valid xml schema.</p>
  
  <p>What is the proper xmlns:og to use to enable FBLike, Comment, and FB Connect?</p>
  
  <p>I know that in the world of HTML 5 this is not important but for the case of older browsers, what should we do?</p>
  
  <p>Thanks!</p>