Lecture #10 looked at game playing, in particular search techniques which can be used by agents engaged in playing games against each other.
Broadly we covered pages 161-171, 173-177. You should, as ever, go through this material carefull to ensure you understand it.
You may also be interested in reading up on two powerful game playing programs. Chinook, which plays Checkers, is described in:
Jonathan Schaeffer, Robert Lake, Paul Lu, Martin Bryant, "Chinook: The World Man-Machine Checkers Champion", AI Magazine, 17(1), 21-29, 1996.You can find out about Deep Blue, which plays chess, and its game against chess World Chamption Gary Kasparov at the official IBM site.