Generating an index in (La)TeX

Making an index is not trivial; what to index, and how to index it, is difficult to decide, and uniform implementation is difficult to achieve. You will need to mark all items to be indexed in your text (typically with \index commands).

It is not practical to sort a large index within TeX, so a post-processing program is used to sort the output of one TeX run, to be included into the document at the next run.

The following programs are available:

makeindex
Comes with most distributions - a good workhorse, but is not well-arranged to deal with other sort orders than the canonical ASCII ordering.

The makeindex documentation is a good source of information on how to create your own index. Makeindex can be used with some TeX macro packages other than LaTeX, such as Eplain, and TeX (whose macros can be used independently with Plain TeX).

idxtex
for LaTeX under VMS, which comes with a glossary-maker called glotex.
texindex
A witty little shell/sed-script-based utility for LaTeX under Unix.

The Texinfo system also uses a program texindex, whose source is to be found in the texinfo distribution. The ltxindex package provides macros to allow LaTeX users to use this texindex.

xindy
arose from frustration at the difficulty of making a multi-language version of makeindex. It is designed to be a successor to makeindex, by a team that included the then-current maintainer of makeindex. It successfully addresses many of makeindex's shortcomings, including difficulties with collation order in different languages, and it is highly flexible. Sadly, its take-up is proving rather slow.
idxtex
indexing/glo+idxtex (zip, browse)
ltxindex.sty
macros/latex/contrib/ltxindex (zip, browse)
makeindex
indexing/makeindex (zip, browse)
makeindex (Macintosh)
systems/mac/macmakeindex2.12.sea.hqx
texindex (the script)
support/texindex (zip, browse)
texindex (the program)
Distributed with macros/texinfo/texinfo (zip, browse)
texsis (system)
macros/texsis (zip, browse)
texsis (makeindex support)
macros/texsis/index/index.tex
xindy
support/xindy/

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