Music notation

Musical notation is a visual record of heard or imagined sound, or a set of visual instructions for performance of music. It usually takes written or printed form and is a conscious, comparatively laborious process. Its use is occasioned by one of two motives: as an aid to memory or as a communication. By extension of the former, it helps the shaping of a composition to a level of sophistication that is impossible in a purely oral tradition. By extension of the latter, it serves a mean of preserving music (although incompletely and imperfect) over long periods of time, facilitates performance by others; and presents music in a form suitable for study and analysis. (Encyclopedia Britannica).