This book presents a systematically outlined theory of synchrotron radiation (SR) and attendant effects. The first part of the book is devoted to fundamental results in synchrotron and undulator radiation theory. This makes it a useful supplement to textbooks on electrodynamics of relativistic particles. The conventional theory is amplified with the recent investigations carried out by the authors. Namely, a semiclassical theory of radiation is developed with regard to the influence of the particle magnetic moment.