title: DTD or XML Schema. Which one is better?
body: <p>What are the pros / cons in DTD and XML Schemas (I'm not even sure what the official name of the latter is!)? Which is better? Why do we need two ways to do the same thing?</p>
  
  <p>Edit: I found this in an article I was reading, which is what prompted me to ask the question:</p>
  
  <blockquote>
    <p>Why W3C XML Schema Language?</p>
    
    <p>The W3C XML Schema Language is not the
    only schema language. In fact, the XML
    specification describes document-type
    definitions (DTDs) as the way to
    express a schema. In addition,
    pre-release versions of the JAXB
    Reference Implementation worked only
    with DTDs -- that is, not with schemas
    written in the XML Schema Language.
    However, the XML Schema Language is
    much richer than DTDs. For example,
    schemas written in the XML Schema
    Language can describe structural
    relationships and data types that
    can't be expressed (or can't easily be
    expressed) in DTDs. There are tools
    available to convert DTDs to the W3C
    XML Schema Language, so if you have
    DTD-based schemas that you used with
    an earlier version of the JAXB
    Reference Implementation, you can use
    these tools to convert the schemas to
    XML Schema Language. <a href="http://java.sun.com/developer/technicalArticles/WebServices/jaxb/#binsch" rel="nofollow noreferrer">http://java.sun.com/developer/technicalArticles/WebServices/jaxb/#binsch</a></p>
  </blockquote>
  
  <p>I guess I would like examples that illustrate why XML-Schema is better (if it indeed is).</p>