If you're looking to win at chess, you need a few things. First, you'll most definitely need lots and lots of practice. Second, you'll need a chess teacher or a chess tutorial. This is actually much easier than it sounds, as there is a popular chess program that is available dirt cheap. It's just one of the things we dig into here at the chess board games blog.

I'm not interested in complete sources, I just want to know how a computer chess game works.

For the high-level overview:
http://electronics.howstuffworks.com/chess1.htm

The pseudo-code:
http://www.mayothi.com/computerschess.html


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