Comment by Jonathan Apodaca on "Has anyone here written the code (or tried to write the code) for a game of chess?"

I am not an authority on this, but my impression was that Chess algorithms use a combination of techniques:

Openings database - the algorithm will keep a database of known good opening moves that get it to a certain point
Brute force - try to predict all possible combinations of moves up until some future point (only do this for the next, say, 10, moves); keep track of the path that maximizes your chances for victory

Here is an interesting read from StackExchange.

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