My Homepage (TM ;) ) contains documents of a more or less technical nature. I use DocBook SGML [docbook.org] for their creation. Redunduncy comes in various ways into play here:
Each document is "rendered" in various formats - HTML, PDF, TXT, PS, RTF to name those known most, but SGML, TEX and LYX are also possible.
Each page contains a header and a footer with "Prev", "Next", "Up" and "Home" links.
A navigation frame with a tree menu structure is always available, unless the user chose to "view frame in window".
Cross linking to chapters, sections, tables, figures, examples is supported perfectly and I make use of it whenever I can. I never say "see the picture below", but rather "see Fig. XX", where XX is calculated automatically by editor (LyX [lyx.org]) and is rendered as a link by the SGML parser (Jade/Openjade [openjade.sourceforge.net]).
There is a Table of Contents (chapter and section titles are links), a List of Figures (figure titles are links to the figures) and an Index (keywords, followed by the link to the relevant chapter, or page for the print formats).
What is important though: redunduncy should not destroy style. *Consistent* formatting is important throughout the pages and the documents. I leave this hard part always to the DSSSL stylesheets [docbook.sourceforge.net]. They take care that, say, an admonition will appear consistently as such with whatever style elements are aproppriate for the format (online or print).
Actually, I don't care about formatting. The DSSSL stylesheets take care of this. I concentrate on content and cross-referencing. The rest is put in place by the stylesheets and I find it good so. It's a good way to separate content from formatting (and to automate the creation of redunduncy a bit by choosing DSSSL stylesheets that create rich navigation elements, like header, footer, table of contents, list of figures and index).
[edited by: tedster at 6:37 am (utc) on Feb. 7, 2003] [edit reason] <remove url> [/edit]