This textbook introduces the topic of special relativity, with a particular emphasis upon light-matter interaction and the production of light in plasma. The physics of special relativity is intuitively developed and related to the radiative processes of light. The book reviews the underlying theory of special relativity, before extending the discussion to applications frequently encountered by postgraduates and researchers in astrophysics, high power laser interactions and the users of specialized light sources, such as synchrotrons and free electron lasers. A highly pedagogical approach is adopted throughout, and numerous exercises are included within each chapter to reinforce the presentation of key concepts and applications of the material.