[texhax] TeX -> PostScript, but in a resolution-independent manner

[Karl Berry]

    What is better, using pdftex to produce PDF directly from TeX files, and 
    then printing it on PostScript printer (converting PDF to PS), or using 
    tex to produce DVI from TeX files and then dvips to convert DVI to 
    PostScript? 

If your goal is to print on a PostScript printer, then you may as well
use tex->dvips.  That has been the de facto standard method on Unix
systems ever since TeX, PostScript, and dvips were invented.

The reason to use pdf(la)tex is if you want pdf files for themselves.

    By the way, is PDF a truely open format, with the full specs
    available, etc. like PS?

It is like PS in that regard.  The specs are on Adobe's web site.  I'm
sure the web sites that Will mentioned have links, etc.