The origins of the pipe organ can be traced back to the hydraulis in Ancient Greece in the 3rd century BC, in which the wind supply was created with water pressure. By the 6th or 7th century AD, bellows were used to supply organs with wind. Beginning in the 12th century, the organ began to evolve into a complex instrument capable of producing different timbres. By the 17th century, most of the sounds available on the modern classical organ had been developed. From that time, the pipe organ was the most complex man-made device, a distinction it retained until it was displaced by the telephone exchange in the late 19th century.
Pipe organs are installed in churches, synagogues, concert halls, and other public buildings and are used for the performance of classical music, sacred music, secular music and popular music. In the early 20th century, pipe organs were installed in theatres to accompany films during the silent movie era, in municipal auditoria, where orchestral transcriptions were popular, and in the homes of the wealthy, equipped with player mechanisms. The beginning of the 21st century has seen a resurgence in installations in concert halls. The organ boasts a substantial repertoire, which spans over 500 years.
– Wikipedia, accessed 2014-09-22