I have been doing some research into artificial intelligence and I came across a 2007 paper titled "Checkers is Solved" on the game of checkers being solved by AI techniques after more than 16 years of trial. A solution to the game is defined by the team as "determining the final result in a game with no mistakes made by either player". The search for a solution started back in 1989 and it was finally found in 2007. Of what importance is this to the field of AI?
When you explore AI, you do so first with a problem space that is relatively small and bounded by specific rules, so that you can prove your techniques.
Checkers is such a space. It therefore makes an ideal playground for AI explorations. This is also true of chess, although checkers is a smaller problem space, and therefore is more suitable to simpler explorations of AI. Board games like chess and checkers are easily modelled in a computer using a two-dimensional array.
As your knowledge improves, you can begin to alter your techniques and apply AI to more complex and non-deterministic domains, like human interactions.