Four Colors Suffice: How the Map Problem Was Solved Book

It looks like it's about maps, but it's really about mathematical proofs. Even though I hate to do math, I like reading about it. This one was a little too dry and technical for me, though, like reading a textbook that tries to be entertaining. The last few pages, though, when a couple of guys actually come up with a proof for this problem, was interesting. I liked reading about the various reactions to their computer-assisted proof; it's an interesting window into the early years of computers and what people thought of them before everyone had one in their homes.