This book is a concise, readable, yet authoritative primer of basic classic thermodynamics. Many students have difficulty with thermodynamics, and find at some stage of their careers in academia or industry that they have forgotten what they learned, or never really understood these fundamental physical laws. As the title of the book suggests, the author has distilled the subject down to its essentials, using many simple and clear illustrations, instructive examples, and key equations and simple derivations to elucidate concepts. Based on many years of teaching experience at the undergraduate and graduate levels, "Essential Classical Thermodynamics" is intended to provide a positive learning experience, and to empower the reader to explore the many possibilities for applying thermodynamics in other fields of science, engineering, and even economics where energy plays a central role. Thermodynamics is fun when you understand it!