This book is ideal for anyone wanting to start scuba diving. It contains the complete theoretical knowledge for the necessary training to gain the Open Water Diver or the Diver 1 star within the CMAS or the R.S.T.C. system and shows some practical examples using small film sequences that can be called up from the Internet using various QR codes. This book does not "burden" with (still) unnecessary knowledge, but leads purposefully to the first internationally recognized diving badge. The new edition also includes the special course diving with Nitrox.