Global navigation satellite systems like GPS or the future European Galileo are influencing the world of navigation tremendously. Today, everybody is concerned with navigation even if unaware of this fact. Therefore, the interest in navigation is increasing. This book provides an encyclopedic view of navigation. Fundamental elements are presented for a better understanding of the techniques, methods, and systems used in positioning and guidance. The book is divided into three parts. Besides a historical review and maps, the first part covers mathematical and physical fundamentals. The second part treats the methods of positioning including terrestrial, celestial, satellite-based, inertial, image-based, and integrated navigation. Routing and guidance are the main topics of the third part. Applications on land, at sea, and in the air are considered. The book is designed for students, teachers, and people interested in entering the complex world of navigation.