All my documents have been typeset using the LaTeX typesetting system. The documents can be downloaded in their source form, the file extension is .tex. The TeX engine, on which LaTeX is based, translates the source file into a .dvi file, a format which is specific to TeX and will only be of use if you have TeX installed on your computer. Since .dvi files are very compact and dvi-previewers are of generally high quality, this is the preferred way for on-line viewing. You can set up your browser to spawn a previewer whenever you click on an URL pointing to a .dvi file.
For more information on how to install and use TeX and LaTeX, see the resource pages maintained by the TeX Users Group.
PostScript is a page description language. It can be used for printing as well as for viewing on-screen. Unlike .dvi files, PostScript files are self-contained documents. They contain the fonts as well as the actual text (thus they tend to be large), so you only need a postscript printer (or a postscript driver for a non-postscript printer) to print the document.
If you are working on a Unix system, you shouldn't experience any difficulties. Download the PostScript file and use lpr (or lp) as usual. You can also set up your browser to spawn ghostview (or another previewer) to start up whenever you click on an URL pointing to a PostScript file.
If you have to use another operating system, there are several options. Adobe Systems provides printer drivers for MS Windows and Mac OS, which can be downloaded for free. I have not tried any of them, but it seems that they require a PostScript capable printer (most laser printers understand PostScript, but many of the less expensive ink jet printers do not). If your printer does not speak PostScript, or you want to view the files on-screen, you can use Ghostscript and GSview, which can be downloaded for free or purchased on a CD.
Alternatively, you can use Linux on your
Mac or PC. Most Linux
Distributions have TeX and PostScript drivers readily set up.
This is what I use at home.