Q. 1. What is a Church organ?

A. 1. A pipe organ contains one or more sets of pipes, a wind system, and one or more keyboards. The pipes produce sound when pressurized air produced by the wind system passes through them. An action connects the keyboards to the pipes. Stops allow the organist to control which ranks of pipes sound at a given time.

According to https://en.wikipedia.org/wiki/Pipe_organ, the Church organ, or Pipe organ consist of the following:

"The pipe organ is a musical instrument that produces sound by driving pressurized air (called wind) through organ pipes selected via a keyboard. Because each pipe produces a single pitch, the pipes are provided in sets called ranks, each of which has a common timbre and volume throughout the keyboard compass. Most organs have multiple ranks of pipes of differing timbre, pitch, and volume that the player can employ singly or in combination through the use of controls called stops.

A pipe organ has one or more keyboards (called manuals) played by the hands, and a pedalboard played by the feet; each keyboard has its own group of stops. The keyboard(s), pedalboard, and stops are housed in the organ's console. The organ's continuous supply of wind allows it to sustain notes for as long as the corresponding keys are pressed, unlike the piano and harpsichord whose sound begins to dissipate immediately after a key is depressed. The smallest portable pipe organs may have only one or two dozen pipes and one manual; the largest may have over 20,000 pipes and seven manuals. A list of some of the most notable and largest pipe organs in the world can be viewed at List of pipe organs.

The origins of the pipe organ can be traced back to the water organ 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. A pipe organ with "great leaden pipes" was sent to the West by the Byzantine emperor Constantine V as a gift to Pepin the Short, King of the Franks, in 757. Pepin's son Charlemagne requested a similar organ for his chapel in Aachen in 812, beginning the pipe organ's establishment in Western church music. In England, "The first organ of which any detailed record exists was built in Winchester Cathedral in the 10th century. It was a huge machine with 400 pipes, which needed two men to play it and 70 men to blow it, and its sound could be heard throughout the city." 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."

Prior to Vatican II, the Pipe Organ was very popular because of its spiritual eloquence. It was found in every Catholic Church. This form of traditional music was considered the music of the angels that harmonized with the Latin Gregorian chant.

Since Vatican II, many Churches removed their Pipe organ and replaced them with a piano on which anyone and everyone could pound on to echo horrible sounds that do not resemble music, nor are worthy of being in the House of God. And some Churches have gone as far as introducing the guitar and other kinds of musical instruments to echo today's modern music world that is more Satanic than divinely inspired.