This book is written for the average student who wants to learn the fundamentals of gas dynamics. It aims at the undergraduate level and thus requires a minimum of prerequisites. The writing style is informal and incorporates ideas in educational technology such as behavioral objectives, meaningful summaries, and check tests. Such features make this book well suited for self-study as well as for conventional course presentation. Sufficient material is included for a typical one-quarter or one-semester course, depending on the studentís background.