Shopper Is this book for people who never dived before?
DIVE S Yes, it is an excellent book. Combined with a competent instructor it will help to be a superior diver.
ANDREW W Yes it is a manual that is used in conjunction with an instructor to teach a first timer how to dive. Not really a learn it on your own type thing. IANTD is one of the best dive certifications that you can obtain. PADI AND NAUI just don't go quite as in depth and pretty much just throw you in the water and teach ya. IANTD has been around for years and will be a leader in the diving world.
Brett H Yes this book is intended for people who have never dove before and are in an IANTD open water diver course, it is the text book for the class.