DocBook is a very popular set of tags for describing books, articles, and other prose documents, particularly technical documentation.
A file is considered to be a DocBook 4 document when one of the following conditions are true:
The default schema, docbookx.dtd, for these documents is stored in [OXYGEN_DIR]/frameworks/docbook/4.5/dtd/.
The default CSS files used for rendering DocBook content in Author mode are stored in [OXYGEN_DIR]/frameworks/docbook/css/.
The default XML catalog, catalog.xml, is stored in [OXYGEN_DIR]/frameworks/docbook/.
To watch our video demonstration about editing DocBook documents, go to http://oxygenxml.com/demo/DocBook_Editing_in_Author.html.