What Happens If an XHTML "meta" Element Is Not Closed?

Meta tags, link tags and base tags must be closed in XHTML documents. If you forget to close them like the HTML format, you will get validation errors. Try the following tutorial sample XHTML document on http://validator.w3.org/ to see what types of errors you will get:

<?xml version="1.0" encoding="UTF-8"?>
<!DOCTYPE html PUBLIC "-//W3C//DTD XHTML 1.0 Strict//EN"
  "http://www.w3.org/TR/xhtml1/DTD/xhtml1-strict.dtd">
<html>
 <head>
  <title>My First XHTML Document</title>
  <base href="http://dev.fyicenter.com/" />
  <meta name="Author" content="FYIcenter.com">
  <meta http-equiv="Content-Type" content="text/html;
    charset=UTF-8" />
  <script type="text/javascript" src="/_local.js"></script>
  <link rel="stylesheet" type="text/css" href="/_fyi.css" />
 </head>
 <body>
 <p></p>
 </body>
</html>

You will get this error:

Error Line 8 column 46: end tag for "meta" omitted, 
  but OMITTAG NO was specified.
  <meta name="Author" content="FYIcenter.com">
You may have neglected to close an element, 
or perhaps you meant to "self-close" an element, 
that is, ending it with "/>" instead of ">". 

Note to HTML 4.0 authors, you must close meta elements in XHTML 1.0. This is the opposite of HTML 4.0, where you must not close meta elements.

⇒ XHTML 'meta' Tag/Element

⇐ Missing XHTML 'title' Element

⇑ HTML Document Structure and Head Level Tags

⇑⇑ HTML Tutorials