Chapter 9. DocBook Markup

Table of Contents
9.1. Introduction
9.2. FreeBSD Extensions
9.3. Formal Public Identifier (FPI)
9.4. Document Structure
9.5. Block Elements
9.6. In-line Elements
9.7. Images
9.8. Links

9.1. Introduction

This chapter is an introduction to DocBook as it is used for FreeBSD documentation. DocBook is a large and complex markup system, but the subset described here covers the parts that are most widely used for FreeBSD documentation. While a moderate subset is covered, it is impossible to anticipate every situation. Please post questions that this document does not answer to the FreeBSD documentation project mailing list.

DocBook was originally developed by HaL Computer Systems and O'Reilly & Associates to be a Document Type Definition (DTD) for writing technical documentation [1]. Since 1998 it is maintained by the DocBook Technical Committee. As such, and unlike LinuxDoc and XHTML, DocBook is very heavily oriented towards markup that describes what something is, rather than describing how it should be presented.

The DocBook DTD is available from the Ports Collection in the textproc/docbook-xml port. It is automatically installed as part of the textproc/docproj port.

Formal Versus Informal:

Some elements may exist in two forms, formal and informal. Typically, the formal version of the element will consist of a title followed by the informal version of the element. The informal version will not have a title.

Inline Versus Block:

In the remainder of this document, when describing elements, inline means that the element can occur within a block element, and does not cause a line break. A block element, by comparison, will cause a line break (and other processing) when it is encountered.

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