The organ is a keyboard instrument in which air moves through pipes to produce sounds. Organs have been used since ancient Greek times and are found in many churches, where they are often used to accompany hymns.
One of the most significant composers of organ music was J. S. Bach. However, organs are not just used in classical music; many rock musicians use electronic organs and pipe organs were used from the 1930s to the 1970s to accompany soap operas on radio and TV.