Web Technology - Old Questions

7.  Compare XML schema with DTD.

Comparison between XML schema and DTD

• XML schemas are written in XML while DTD are derived from SGML syntax.
• XML schemas define datatypes for elements and attributes while DTD doesn't support datatypes.
• XML schemas allow support for namespaces while DTD does not.
• XML schemas define number and order of child elements, while DTD does not.
• XML schemas can be manipulated on your own with XML DOM but it is not possible in case of DTD.
• using XML schema user need not to learn a new language but working with DTD is difficult for a user.
• XML schema provides secure data communication i.e. sender can describe the data in a way that receiver will understand, but in case of DTD data can be misunderstood by the receiver.
• XML schemas are extensible while DTD is not extensible.