XML (eXtensible Markup Language)

XML is a W3C-recommended general-purpose markup language that supports a wide variety of applications, and is extensible. XML is a simplified subset of Standard Generalized Markup Language (SGML). DITA is a "dialect" of XML.

The following figure shows a simple, annotated XML file.

The following figure shows the XML object model for the simple XML file.

The following figure shows a simplified tree structure model for a typical DITA project.

Related concepts
DOCTYPE declaration
DTD (Document Type Definition)
Schema
Related information
http://www.w3c.org