An entire chapter in this title is devoted to applications of the theory to elucidate a large number of topics the students (B.Sc. Physics) come across in Modern Physics. Detailed and well-selected examples are used to illuminate aspects of the theory as well as to show techniques of application. A large number of Illustrative Examples enables the students to gain confidence to solve any problem in relativity normally expected of B.Sc. students. The Book meets the complete requirements of a textbook for B.Sc. General and Honours courses in special theory of relativity recommended by the U.G.C. Existing syllabi in a number of our universities have been taken into account in planning the book. The structure of the book permits a lot of flexibility. The book can therefore be used as a text for a number of existing courses (with different allotted periods) presently prevalent in many Indian Universities.