There are more than ten thousand particle accelerators in the world ranging from the linear accelerators used for cancer therapy in hospitals to the giant "atom smashers" at international particle physics laboratories which reveal the secrets of creation. Many scientists and engineers spend their lives designing, constructing, and running these machines, yet few universities include a study of them in their curricula. This book is a straightforward introduction which can be used by the big accelerator laboratories. It covers the essentials of the subject for the many who need to learn how these machines work and how to run them. It treats each of the aspects of a modern accelerator giving enough information to understand the subject without overloading the reader with excess mathematics or theory. The text includes a selection of exercises and answers to encourage a full understanding.