Quench?

Alright, I'll be the dummy for the day. I have heard the term, quench, when reading about engine builds. I'll cop out and admit, I haven't got the slightest idea of what quench is, what it does or if it just means you guys are thirsty.

Don't all of you laugh at once and don't beat me up too bad. I am about to start a build, in the next couple of months, and I want to learn as much as possible so I can make you all proud. I have asked for help and a couple of guys on this board have offered their expertise, I just don't want to wear them out with every little question I have. I will come to the board to ask about stuff and I know that I'll get good answers. Now, what is quench? I have only done or helped with a couple of stock rebuilds but I have never heard of, quench.#-o