Musical symbols are the components of the notation system that is used in scores to indicate how a composer or arranger intends a musical composition to be performed. A large number of such symbols exists, and they can indicate virtually every detail for each instrument or group of instruments for each unit of time in a work, including pitch, volume, tempo and playing technique.
The use of musical symbols in Western music began in a very simple form around the thirteenth century. Although this system was largely standardized throughout the common practice era, it has subsequently continued to evolve, mainly though the use of additional symbols, as a result of both the development of new playing techniques for existing instruments and the development of new instruments.