This article is from the Amiga FAQ, by Ignaz Kellerer with numerous contributions by others.
TeX is a very powerful wordprocessing system. It can display mathematical formulas or complex tables as well as function graphs, creates indices, contents and many other things. Its greatest advantage is that it is freely distributable (TeX, not the previewers and the printer drivers!) and that you find TeX all over the world on every computer family. Its greatest disadvantage is that it isn't very handy (works similar to a compiler) and it isn't wysiwyg. But many people like it. (BTW: This document is written using TeX. 8-) See Word Processors.
There are two major implementations on the Amiga. The first one, Amiga-TeX, from Thomas Rockicki and Radical Eye software is commercial. It is said to be excellent and his owners seem to be very satisfied. But it costs at least 200$.
I recommend PasTeX, a freely distributable version. People seem to have problems installing PasTeX, especially the font loading and generation (It's a quite complex program.) but I did not here anyone upset once it was installed. (A friend with knowledge of TeX helps immensely.) A few words should be said what you need: * 5 disks containing the TeX-compiler itself
* 2 disks containing MetaFont
* Nothing more Jörgen Grahn has written a short essay on how he personally did to make LaTeX work on his Amiga. It's on Aminet as `text/tex/UsingLaTeX.lha'.
Many people ask for fonts. They are included in the MetaFont-package and can get compiled by you. All you need to do is setting up your TeX-system in the right way which is described in the documentation. Please note that the PasTeX disks are compressed using the program Zoom. (see Endings) Sources: FTP at `ftp.uni-passau.de', directory `/pub/amiga/tex/PasTeX1.3' and the Fish CDs.