By the early twenty-first century, Western musical notation has developed into an extraordinarily rich and complex piece of visual communication. Modern musicians expend considerable time and energy to create strategies for its more efficient comprehension. Simultaneously, musicians are continuously inventing new symbols and systems of symbols for two very different reasons. Some wish to communicate with ever greater precision the instructions necessary for the reproduction of a musical work. Others are seeking ways of recording in writing musics whose origins are not necessarily rooted in notation. Charles Seeger identified these two streams as, respectively, “prescriptive” and “descriptive” forms of notation.