This thoroughly revised book, now in its Fourth Edition, continues to provide a comprehensive introduction to this increasingly important area of nuclear and particle physics. It combines coverage of basic concepts, principles and applications, along with the latest developments. Beginning with the historical developments of the subject, properties and constituents of the nucleus, quantitative facts about nucleus, etc., the book moves on to give insights into nuclear models, phenomenon of radioactivity and its applications in various fields, nuclear reactions including reactions in the Sun and stars, photoelectric and Compton effects, pair creation, different particle accelerators and radiation detectors. Full chapter is also devoted to present an extensive discussion on elementary particles and their fundamental interactions, giving their properties, quantum numbers, basic conservation laws controlling particles decays and interactions, and the quark model. In this present edition, some sections have been revised and enlarged to enhance their comprehension, besides including several new solved and unsolved problems. The text is designed for the students of B.Sc. (Physics), though it can also serve as introductory review material for M.Sc. (Physics) students. KEY FEATURES Contains actual experimental data Large number of solved problems to help students comprehend the concepts with ease Provides unsolved problems with answers and review questions to test the students’ comprehension of the subject