The harmonium, part of the reed organ family, is a free-reed keyboard instrument, a close cousin of the pipe organ. The harmonium was developed during the middle of the nineteenth century to meet the burgeoning demand for a relatively inexpensive organ-like instrument for home and chapel. It, or its American development, the "American Organ" or "Cabinet Organ", is still sometimes used in churches and auditoriums to replace an organ because the latter is too expensive.
When the harmonium is played, there are foot pedals that the organist pushes to blow air through the free reeds.
The harmonium is also played in India to accompany traditional singing. Here, it is small, played on the floor, and the air is blown into the reeds by a small bellows with one hand, while the other hand plays the keyboard.