The nature of classical music.
Classical music is primarily a written musical tradition, preserved in music notation, as opposed to being transmitted orally, by rote, or in recordings. While differences between particular performances of a classical work are recognized, a work of classical music is generally held to transcend any particular performance thereof. Works that are centuries old can be, and often are, performed far more often than works recently composed. The use of notation is an effective method for classical music because all active participants in the classical music tradition are able to read music and are schooled in the current performance practices. Normally, this ability comes from formal training, which usually begins with learning to play an instrument, and sometimes continues with instruction in music theory and composition. However, there are many passive participants in classical music who enjoy it without being able to read it or perform it.
Classical music is meant to be experienced for its own sake. It is unlike other forms of music that serve as a vehicle for poetry or other lyrical content, or as an adjunct to other forms of entertainment. Performances of classical music often take place in a relatively solemn atmosphere, with the audience expected to maintain silence and remain immobile during the performance, so that everyone can hear each note and nuance. The performers usually dress formally, a practice, which is often taken as a gesture of respect for the music, and performers normally do not engage in casual banter or other direct involvement with the audience.
Written transmission, along with the veneration bestowed on classical works, has important implications for the performance of classical music. To a fair degree, performers are expected to perform a work in a way that realizes the original intentions of the composer, which are often stated quite explicitly (down to the level of small, note-by-note details) in the musical score. Indeed, deviations from the composer's intentions are sometimes condemned as outright ethical lapses. 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.
Another consequence of the veneration 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, 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--but tended to write out the cadenzas when other soloists were to perform them.
Art music and concert music are terms sometimes used as synonyms of classical music.
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