The Original Hacker's Dictionary. [This file, jargon.txt, was maintained on MIT-AI for many years, before being published by Guy Steele and others as the Hacker's Dictionary.
Many years after the original book went out of print, Eric Raymond picked it up, updated it and republished it as the New Hacker's Dictionary. Unfortunately, in the process, he essentially destroyed what held it together, in various ways: first, by changing its emphasis from Lisp-based to UNIX-based (blithely ignoring the distinctly anti-UNIX aspects of the LISP culture celebrated in the original); second, by watering down what was otherwise the fairly undiluted record of a single cultural group through this kind of mixing; and third, by adding in all sorts of terms which are "jargon" only in the sense that they're technical.
This page, however, is pretty much the original, snarfed from MIT-AI around 1988. -- jpd.] Find the Meanings and Definitions of Words at Dictionary. Webopedia: Online Computer Dictionary for Computer and Internet Terms and Definitions.