(La)TeX conversion to HTML

TeX and LaTeX are well suited to producing electronically publishable documents. However, it is important to realize the difference between page layout and functional mark-up. TeX is capable of extremely detailed page layout; HTML is not, because HTML is a functional mark-up language not a page layout language. HTML's exact rendering is not specified by the document that is published but is, to some degree, left to the discretion of the browser. If you require your readers to see an exact replication of what your document looks like to you, then you cannot use HTML and you must use some other publishing format such as PDF. That is true for any HTML authoring tool.

TeX's excellent mathematical capabilities remain a challenge in the business of conversion to HTML. There are only two generally reliable techniques for generating mathematics on the web: creating bitmaps of bits of typesetting that can't be translated, and using symbols and table constructs. Neither technique is entirely satisfactory. Bitmaps lead to a profusion of tiny files, are slow to load, and are inaccessible to those with visual disabilities. The symbol fonts offer poor coverage of mathematics, and their use requires configuration of the browser. The future of mathematical browsing may be brighter - see future Web technologies.

For today, possible packages are:

LaTeX2HTML
a perl script package that supports LaTeX only, and generates mathematics (and other "difficult" things) using bitmaps. The original version was written by Nikos Drakos for Unix systems, but the package is now also available for Windows systems. Michel Goossens and Janne Saarela published a detailed discussion of LaTeX2HTML, and how to tailor it, in TUGboat 16(2).
TtH
a compiled program that supports either LaTeX or plain TeX, and uses the font/table technique for representing mathematics. It is written by Ian Hutchinson, using flex. The distribution consists of a single C source (or a compiled executable), which is easy to install and very fast-running.
Tex4ht
a compiled program that supports either LaTeX or plain TeX, by processing a DVI file; it uses bitmaps for mathematics, but can also use other technologies where appropriate. Written by Eitan Gurari, it parses the DVI file generated when you run (La)TeX over your file with tex4ht's macros included. As a result, it's pretty robust against the macros you include in your document, and it's also pretty fast.
TeXpider
a commercial program from Micropress, which is described on http://www.micropress-inc.com/webb/wbstart.htm; it uses bitmaps for equations.
Hevea
a compiled program that supports LaTeX only, and uses the font/table technique for equations (indeed its entire approach is very similar to TtH). It is written in Objective CAML by Luc Maranget. Hevea isn't archived on CTAN; details (including download points) are available via http://pauillac.inria.fr/~maranget/hevea/
The World Wide Web Consortium maintains a list of "filters" to HTML, with sections on (La)TeX and BibTeX - see http://www.w3.org/Tools/Word_proc_filters.html
latex2html
Browse support/latex2html/
tex4ht
support/TeX4ht/tex4ht.zip
tth
nonfree/support/tth/dist/tth_C.tgz