Warez doesn't stand for for anything. It means games (that are still for sale) illegally distributed over the internet.
HOTU is Home of the Underdaos, another games site
http://www.the-underdogs.org
AB means ABandonia and AR means Abandonia Reloaded, our sister site (
http://www.reloaded.org )
There are other, more common, internet internet abbreviations, Have a look:
http://en.wikipedia.org/wiki/Leet