Sheet Music - Written Notation 

Sheet music is the written notation of how to play a musical piece. It can be as simple as the six lines notating the melody of the song to a full orchestral score for multiple different instruments. It's first use was for what we now call Classical Music but it is now standardised for common use and has been since the 16th century.

Classical music is considered primarily a written musical tradition, preserved in music notation, as opposed to being transmitted orally, by rote, or in recordings of particular performances. While there are differences between particular performances of a classical work, a piece of classical music is generally held to transcend any interpretation of it.

The use of musical notation is an effective method for transmitting classical music, since the written music contains the technical instructions for performing the work. The written score, however, does not usually contain explicit instructions as to how to interpret the piece in terms of production or performance, apart from directions for dynamics, tempo and expression (to a certain extent); this is left to the discretion of the performers, who are guided by their personal experience and musical education, their knowledge of the work's idiom, and the accumulated body of historic performance practices.

However, improvisation once played an important role in classical music. A remnant of this improvisatory tradition in classical music can be heard in the cadenza, a passage found mostly in concertos and solo works, designed to allow skilled performers to exhibit their virtuoso skills on the instrument. Traditionally this was improvised by the performer; however more often than not, it is written for (or occasionally by) the performer beforehand.

Its written transmission, along with the veneration bestowed on certain classical works, has led to the expectation that performers will play a work in a way that realizes in detail the original intentions of the composer. During the 19th century the details that composers put in their scores generally increased.

Yet the opposite trend — admiration of performers for new "interpretations" of the composer's work — can be seen, and it is not unknown for a composer to praise a performer for achieving a better realization of the composer's original intent than the composer was able to imagine. Thus, classical music performers often achieve very high reputations for their musicianship, even if they do not compose themselves. Generally however, it is the composers who are remembered more than the performers.

Another consequence of the primacy of the composer's written score is that improvisation plays a relatively minor role in classical music, in sharp contrast to traditions like jazz, where improvisation is central.

Improvisation in classical music performance was far more common during the Baroque era than in the nineteenth and twentieth centuries, and recently the performance of such music by modern classical musicians has been enriched by a revival of the old improvisational practices.

During the classical period, Mozart and Beethoven sometimes improvised the cadenzas to their piano concertos (and thereby encouraged others to do so), but they also provided written cadenzas for use by other soloists.