Music theory is the study of music, including how it is composed and its effects on people (and possibly on other living organisms). It makes use of other sciences and social sciences, including mathematics, physics, psychology, anthropology, and even theology. Although studying music theory is often regarded as a chore by composers, a knowledge of it can be very useful in helping them to achieve the effects they desire. Such knowledge can likewise be useful for performers to help them improve their performance, and even for ordinary people in raising their level of music appreciation.
Examples of the many diverse aspects of music theory include the science of harmonic systems, harmony, counterpoint, instrument structure, materials and timbre, acoustics, effects of religion on the historical development of music, and the effects of music education on childhood development
Other aspects of music study that are often classified together with theory but might rather be considered less theory and more practical aspects, include reading and writing of music notation, techniques for playing and maintaining specific instruments, and composing.