4.2 Structuring Command Types ¶

The chapter structuring commands fall into four groups, each of which contains structuring commands at the levels of chapters, sections, subsections, and subsubsections:

• The @chapter-like commands and @appendix-like commands produce numbered or lettered entries both in the body of a document and in its table of contents.
• The @unnumbered-like commands produce unnumbered entries both in the body of a document and in its table of contents. The @top command, which has a special use, is a member of this group (see The @top Sectioning Command). An @unnumbered section is a normal part of the document structure.
• The @heading-like commands produce simple unnumbered headings that do not appear in a table of contents, are not associated with nodes, and cannot be cross-referenced. These heading commands never start a new page.

In printed output, the chapter structuring commands produce headings in the document. When a @setchapternewpage command says to do so, the @chapter, @unnumbered, and @appendix commands start new pages in the printed manual; the @heading commands do not. See @setchapternewpage: Blank Pages Before Chapters.

In Info and plain text output, the command causes the title to appear on a line by itself, with a line of an ASCII character (‘*’, ‘=’, …) inserted underneath. For example, the “Chapter Structuring” heading could be:

5 Chapter Structuring
*********************

The underlining character is the same for all the commands at the same level. For instance, it is the same for the chapter-level commands @chapter, @apppendix, @unnumbered and @chapheading.

In HTML, the chapter-level commands produce an <h2>-level header by default (controlled by the CHAPTER_HEADER_LEVEL customization variable, see Other Customization Variables). The heading element level is adjusted for the other commands.

In the DocBook output, the appropriate level of element is used. The produced element includes all following sections up to the next command at the same or higher level. For example, a <chapter> element is produced for @chapter, and contains any sections or subsections in the chapter.

Here is a summary: