XInclude is a standard for building XML documents from smaller pieces and is an
alternative to the use of external entities. The use of external entities can pose a
problem because they cannot have a DOCTYPE declaration, and therefore are not valid
documents on their own.
XInclude is mainly used in documentation frameworks where the documents may be
composed of numerous files. XInclude allows you to validate the Master File as well as
The advantages of modular documentation include reusable content units, smaller
file units to be edited, better version control, and distributed authoring.
XInclude in oXygen
In the following images, you see an example of a chapter file named
chapter1.xml and a book file that uses XInclude to reference the
Chapter file chapter1.xml:
Main book file: