Not a bad introduction to linguistics. It does a good job of outlining the main branches: how does language arise, why is the human brain so good at learning language, how do languages evolve and how are current languages related.
I generally like the graphic guide format. In this book, though, the format seemed to encourage more focus on personalities than one might like. But that’s a minor quibble. It serves its purpose: to introduce a complex subject in an easily digestible form.