This book is a complete guide to Saturn and our current understanding of it. Saturn takes a path from the early history of the development of our understanding of the most distant planet seen by naked eye observations, and brings the reader to a position of being informed of the latest results and current understanding of this giant planet, its rings and satellites. In the first part of this book, the authors provide a background for the Saturn systems, building on the initial activities of Cassini and Huygens, whose fundamental activities 350 years ago provided a firm basis for our current knowledge. These historical discussions set the scene of the issues of the time, and the fundamental matters that concerned them. They shaped our knowledge with their major discoveries using very basic instruments. There follows an explanation of our understanding of Saturn, its rings, satellites and environment developed from centuries of ground-based - and now spacecraft - observations from Voyager, Cassini and space-borne telescope systems on Hubble. The penultimate part of the book looks at the current state of our understanding of the Saturn system and Titan (its largest moon), and identifies the many questions which still remain unresolved.