The present work is a very clear, concise and authoritative exposition of both the special and general theories of relativity. Intended for nonscientific readers with a knowledge of high school math, the book offers illuminating coverage of such topics as the speed of light, simultaneity, time distortion, distortion of space and mass, journeys to the stars, dimensions and hyperspace, the theory of general relativity, anomalies in space, and the structure and evolution of the universe.