To get an overview of a documents contents, a table of contents should be available, from which every section can be accessed directly. This can be done with PDF and HTML, when converting LATEX to HTML, the hyperref macros can do this job automatically.
Sometimes the table of contents gets quite long. When converting into HTML, it's recommended to divide the table of contents into two levels. The main table on the first level only displays chapter headings, linking to a table of contents only for this chapter on the second level. Figure 21 illustrates this splitting of the table of contents.
As for navigating, the chapter's tables of contents on the second level should be linked into a circular list (with references to the next/last chapter), just as regular pages are, see Figure 22.
As with the regular pages, a ``back''-link from the first page and a ``next''-link from the last page may be omitted. However, ``up''-links should be available, pointing to the first level table of contents.