Glossary Updates6 new terms added to the glossaries · October 11, 2026, 13:38 CEST
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Glossary · 4 · Structure and semantics

DocBook

Also known as: DocBook schema, DocBook XML

DocBook is a general-purpose XML schema for technical and software documentation, especially books and articles, maintained by the OASIS DocBook Technical Committee; it began in 1991 as an SGML document type of HaL Computer Systems and O’Reilly & Associates and has been defined in RELAX NG with Schematron rules since version 5.0.

  • Structured authoring
  • Markup
  • Standards

In one sentence

DocBook is an OASIS-maintained XML schema for technical books and articles, begun in 1991 and defined in RELAX NG since version 5.0.

Example

A software manual written in DocBook consists of a book element with chapters, sections, procedures with steps, program listings and a glossary; one source is transformed with stylesheets into HTML, PDF and EPUB.

How it applies

  • History: According to DocBook: The Definitive Guide, DocBook began in 1991 as a joint project of HaL Computer Systems and O’Reilly & Associates, primarily to exchange UNIX documentation originally marked up in troff. Its maintenance passed to the Davenport Group and, in mid-1998, to a Technical Committee of OASIS. Versions up to 4.x were SGML and XML DTDs; starting with version 5.0, DocBook is exclusively an XML vocabulary defined with RELAX NG and Schematron.
  • Status: DocBook 5.1 was approved as an OASIS Standard on November 22, 2016. The Technical Committee has since published DocBook 5.2 as a Committee Specification. The termCode names the latest version that is an OASIS Standard.
  • In documentation practice: DocBook is used for software manuals, technical books and reference documentation that is published as books, web pages and e-books from one source. Its elements are mostly document-domain structures — book, chapter, section, procedure, step, table — together with many inline elements for software (commands, options, file names). Customization layers restrict or extend the schema.
  • Machinery documentation: DocBook can carry operating and maintenance instructions, but it defines no industry-specific safety structures; organizations that need them add their own elements or rules. Using DocBook does not make documentation compliant with any requirement for instructions.

DocBook vs. DITA

DocBook is book-oriented: a document is a hierarchy of components such as book, part, chapter and section, and reuse works mainly through modular files and XInclude. DITA is topic-oriented: content is written as typed topics such as DITA task, DITA concept and DITA reference and assembled into deliverables by DITA maps; it extends its vocabulary by specialization. Both are OASIS standards and both support single-sourcing.

External references