Proposed Extensions to XML

A number of XML extensions have already been proposed. All use the XML language itself as the basis for describing extensions to XML documents and processors.

• DOM - Document Object Model - This API is a stable, proposed recommendation that provides a platform and language-neutral interface to dynamically access and update the content, structure and style of XML documents.
• XSL - eXtensible Stylesheet Language - This language is composed of transformation rules that allow you to flexibly map structures and specific Elements and Attributes in XML documents to arbitrary results. For example, you could simply write rules to translate XML into HTML.
• XLink - XML Linking Language - This language uses XML syntax that can be inserted into XML resources to describe unidirectional hyperlinks (like today's HTML) as well as more sophisticated multi-ended and typed links.
• XPointer - XML Pointer Language - This language supports addressing the internal structures of XML documents, whether or not they bear the explicit ID attribute.
• DCD - Document Content Description for XML - This language proposes a structural schema facility using XML syntax, which replaces the function of the DTD in supplying document constraints, and grammar. It also provides a key additional property of providing datatypes. DCD incorporates a subset of XML-Data, and is an RDF vocabulary.