organ (music)

The organ is a keyboard instrument played using one or more manuals and a pedalboard. It uses wind moving through metal or wood pipes and/or it uses sampled organ sounds or oscillators to produce sound, which remains constant while a key is depressed. Its sounds, which vary widely in timbre and volume, are divided according to ranks and controlled by the use of stops. The keyboard is not expressive and does not affect dynamics. Organs vary greatly in size, ranging from a cubic yard to a height reaching five floors , and are located primarily in churches, concert halls, and homes. The organ is one of the oldest musical instruments in the Western musical tradition, and carries a rich history connected with Christian liturgy and civic ceremony.
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The organ repertoire consists of music written for the  organ. Because it is one of the oldest musical instruments in existence, written organ repertoire spans a time period almost as long as that of written music itself. The organ's solo repertoire is among the largest for any musical instrument. Because the organ was found almost exclusively in the western churches from the Middle Ages until the emergence in the Romantic era of large concert hall instruments, a significant portion of organ repertoire is sacred in nature. Thus, most organ music comes from Western Europe and North America; because the eastern religions (such as the Eastern Orthodox Church) did not use any instruments in their worship. Owing to the age of the instrument and its frequent use in Western worship, the organ has one of the most varied repertoires of any instrument.
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