Chapter 8. XHTML Markup

Table of Contents
8.1. Introduction
8.2. Formal Public Identifier (FPI)
8.3. Sectional Elements
8.4. Block Elements
8.5. In-line Elements

8.1. Introduction

This chapter describes usage of the XHTML markup language used for the FreeBSD web site.

XHTML is the XML version of the HyperText Markup Language, the markup language of choice on the World Wide Web. More information can be found at

XHTML is used to mark up pages on the FreeBSD web site. It is usually not used to mark up other documentation, since DocBook offers a far richer set of elements from which to choose. Consequently, XHTML pages will normally only be encountered when writing for the web site.

HTML has gone through a number of versions. The XML-compliant version described here is called XHTML. The latest widespread version is XHTML 1.0, available in both strict and transitional variants.

The XHTML DTDs are available from the Ports Collection in textproc/xhtml. They are automatically installed by the textproc/docproj port.


This is not an exhaustive list of elements, since that would just repeat the documentation for XHTML. The aim is to list those elements most commonly used. Please post questions about elements or uses not covered here to the FreeBSD documentation project mailing list.

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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