The idea of writing an easy-to-read, yet complete, GPS book evolved during my industrial employment term during the period from 1996 to 1997. My involvement in designing and providing short GPS courses gave me the opportunity to get direct feedbacks from GPS users with a wide variety of expertise and background. One of the most difficult tasks, which I encountered, was the recommendation of an appropriate GPS reference book to the course attendees. Giving the fact that the majority of the GPS users are faced with a very tight time, it was necessary that the selected GPS book be complete and easy-to-read. Such a book did not exist.