The textbook "Fundamentals of Music Processing" offers a comprehensive introduction to the technologies and fundamental topics of music processing and music information retrieval (MIR). It is aimed at students, educators, and researchers in the fields of audio engineering, signal processing, computer science, digital humanities, and musicology. The content is supplemented with numerous examples, illustrations, and exercises, which facilitate the understanding of the complex subject matter. The book is divided into eight chapters, ranging from the basics of music representation to mathematically grounded techniques and algorithms applicable to a variety of analysis, classification, and retrieval problems. The blend of theory and practice aims to provide in-depth technological insights and a solid understanding of applications in music processing.