There is science behind every aspect of music and music making. What is sound? How does it travel? How do we make musical sounds, with musical instruments, recordings, or electronics? What makes a good concert hall? How is music sent over the Internet? How does a trumpet work, or a synthesizer, or the human voice? This book addresses all these questions and more, offering a comprehensive introduction to the scientific study of music that draws on ideas from physics, biology, mathematics, and engineering to explain how music works. Using some mathematics but avoiding calculus, the book offers a step-by-step discussion of the science of music, starting with the nature of sound waves, and covering musical pitch and scales, sound energy and loudness, harmonics and timbre, the human ear, room acoustics, digital sound, recording technology, and the workings of a wide range of musical instruments, from traditional string and wind instruments to contemporary workhorses such as electric guitar and electronic instruments. The book is suitable for instructors or students studying the science of music at the undergraduate level, or for any scientifically curious reader who wishes to learn about this intriguing field.