This book is an amazing read for those wanting to learn about linguistics. It has clear examples and explanations, it covers every topic, from the theories about the origin of the language, phonetics or phonology, on to pragmatics, discourse and the like.
Obviously, it is not a thorough linguistics manual, it is for beginners, so to speak. But there's no better starting point than this. Every concept is introduced with really helpful examples, so it's easy to grasp everything. As an analogy, this is like a "popular science" book: it does not use special vocabulary without introducing it first, it assumes little prior knowledge fromt he reader, etc.
The choice of colour and font is superb as well. It always helps reading the book.