title: Must xml documents have a root tag?
body: <p>I wrote the w3cschool quiz on xml documents and it said I was wrong that xml documents need a root tag. After searching around I found <a href="http://www.w3schools.com/xml/xml_syntax.asp" rel="nofollow">this article</a> which states </p>
  
  <blockquote>
    <p>XML documents must contain one element that is the parent of all other
    elements. This element is called the root element.</p>
  </blockquote>
  
  <p>Isn't this a contradiction or what's the difference? </p>
  
  <p>The result of the question on the quiz was </p>
  
  <blockquote>
    <ol start="9">
    <li>Which statement is true?</li>
    </ol>
    
    <p>You answered: XML documents must have a root tag</p>
    
    <p>Wrong Answer!</p>
  </blockquote>