This book came about from trying to convince various friends that math is fun and cool. I realize saying “math is cool” is probably not cool. But saying math is fun, or math is interesting, or math is neat, well, those don’t sound all that cool either. Anyhow, I always do my best to show people what it is I like about math, and finally I decided to write a book about that. Georgia Kennedy was the person who finally got me to start this project. She’s an artist and as many good artists, she’s interested in all things, which for me fortunately includes math. Early scribbles on napkins at River Gods led to this book. - David Craft.