Gas dynamics and space propulsion has become a core subject for students of mechanical engineering in many universities. Gas dynamics forms the basis for the study of aerodynamics. This book covers the basics of compressible fluid flow with fluid mechanics, thermodynamics and heat transfer principles. It discusses in detail gas dynamics under different flow conditions with and without heat transfer and friction. The subject has been made simple and easy to understand with practical applications, figures and graphs. Students studying the subject at the undergraduate level and also teachers will find this book to be a guide and good reference.