This second edition of Engineering Thermodynamics is designed as a textbook for undergraduate students of Mechanical Engineering. A self-study text, it provides an in-depth coverage of the fundamental principles of thermodynamics. While providing the mathematical representation, it also lays emphasis on the physical aspects of the subject. Starting with the basic concepts, the book goes on to discuss important topics such as entropy, thermodynamic availability, properties of steam, real and ideal gas, power cycles, and chemical equilibrium in increasing order of complexity. A lucid exposition of the fundamental concepts of thermodynamics in the book along with numerous worked-out examples and well-labelled detailed illustrations are sure to instil in the beginners a holistic understanding of the subject.