Music theory
Music theory is the study of theoretical frameworks for understanding the practices and possibilities of music. The Oxford Companion to Music describes three interrelated uses of the term "music theory": The first refers to the "rudiments" needed to understand music notation such as key signatures, time signatures, and rhythmic notation; the second is a study of scholars' views on music from antiquity to the present; the third is a sub-topic of musicology that "seeks to define processes and general principles in music".