title: Self-closing tags in XML files
body: <p><code>&lt;tag id="foo" /&gt;</code></p>
  
  <p>I noticed that they work with PHP SimpleXML.</p>
  
  <p>But all XML examples I found on the web close them the old way:</p>
  
  <p><code>&lt;tag id="foo"&gt;&lt;/tag&gt;</code></p>
  
  <p>Is there any reason why I should use the old method?</p>