XML Language Elements
Document Type Definition (DTD), which defines the tags and their relationships
Extensible Style Language (XSL) style sheets, which specify the presentation of the document
Extensible Link Language (XLL), which defines link-handling details
It supports scripting languages such as ECMAScript (JavaScript) or Java
For example a link can be defined in XML as <LINK> <TITLE>XML Recommendation</TITLE> <URL> http://www.w3.org/TR/REC-xml </URL> <DESCRIPTION> The official XML spec from W3C </DESCRIPTION> </LINK>