Starting with the basic concepts, the book gradually discusses the important topics like entropy, thermodynamic availability, properties of steam, real and ideal gas, and chemical equilibrium in the increasing order of complexity. It lays emphasis on the physical aspects of the subject matter in addition to the mathematical representation to develop an in-depth understanding of the subject. The focus of the book is to provide a clear exposition of the fundamental principles of thermodynamics by presenting adequate information in a lucid style to endow the beginners a reasonable understanding of the subject. The text covers syllabi requirements of almost all technical universities in India and will also cater to the needs of the graduate level students of the world over, and be useful as a reference book to practicing engineers. Abundant worked-out examples, numerical problems, review questions, and multiple choice questions form the special feature of the book.