The organ is a wind instrument played from a keyboard. The tone of the organ is produced by pipes made of metal or wood. Sound is then created by compressed air flowing through the pipes. A single pipe is able to produce a single note of only one tone. Organ pipes vary in length from a few inches to more than 32 feet. The organ pipes are organized into "ranks" - a set or row of pipes for each of the "stops" of the organ. These rows of pipes always have the same kind of sound. For example, all the pipes for a Spitzflute (one kind of flute sound) will be in the same rank and are played from the same “stop”. Stops are the labeled white push/pull knobs you see on the organ console to the sides of the keyboard

The pipes of each division stand on a windchest. The windchest contains the apparatus by which valves under the pipes are opened, by pressing a key at the organ console, letting wind into them and causing them to speak. The wind is delivered to the windchest from the reservoir, a bellows-like box, which serves to steady the wind and give it a predetermined and constant pressure. The reservoir, in turn, receives the wind from the blower, a large fan driven by an electric motor.