Checkers is a very easy game, but with those incredibly simple rules you can get complex behavior. For an even more extreme example, you can look at Go. Git is similar, except there is no competition/competitor there to befuddle you. From the simple components/rules (you've got what, you can perform incredibly complex operations that are infeasible with lesser VCSs.

Simple rules/components, complex gameplay/capability.

If you want to play it simple, git does that too.