Written by Attila K. Kollár, this book targets students of beginner UEF diving courses, but it may also be an interesting read for any diver or anyone interested in diving. The ten chapters in the book provide fundamental and most crucial knowledge for divers, and even go a bit beyond the basics: supplementary information adds colour, creates interest and puts the basic knowledge of diving into more perspective. At the end of the book, tests are provided to check knowledge acquired in each chapter, with the solutions available. Most of the theoretical knowledge can be learnt from the book, but comprehensive instruction also calls for additional materials, such as a CD-ROM and the relevant regulations, as well as the instructor's presentations and consultations. The diving instructor administers practical training, swimming pool (confined water) and open water dives, preparation for which is covered in the relevant parts of this book. The book "Open Water Diver" may come useful even after a diver has completed the course, just to refresh knowledge.