This book is about randomly generating mazes by writing computer programs. Before reading this book, I'd tried randomly generating some mazes, but those mazes hadn't pleased me: too many little nubbly dead ends. This book showed an algorithm (well, a few algorithms) that didn't have so many dead ends. (The secret, obvious when you hear it but I swear not so obvious when you're just staring at a maze and trying to figure out what you don't like about it: have fewer branches in the maze.)
There's plenty in this book: several maze-generation algorithms, tweaks for hex grids, tweaks for 3-D, tweaks for cylinders, tweaks for… Uhm, yeah, there's plenty in this book. I didn't use much of it. I was just looking for this one specific thing! But it's nice to know that if I ever want to put a maze on a Möbius strip, this book has some ideas about that.