A class of aerophones using enclosed reeds. The bagpipe is a folk instrument of ancient origins, probably from the Middle East.

An animal bladder comprises the 'bag' which is held under the player's arm and acts as a reservoir of air. The player, called a piper, then blows into it through a mouth pipe and keeps up the pressure with his arm. Several pipes lead off from the bag: the melody pipe with finger holes and two or three drone pipes (drone pipes were added during Medieval times). All the pipes are activated by a reed. The mouth pipe is fitted with a non-return valve so that air cannot escape.