A drum is a musical percussion instrument, consisting of a membrane which is usually stretched taut over a cylindrical tube that is open at the other end. The membrane is struck, either with the hand or some other object like a drumstick, and the tube forms a resonating chamber for the resulting sound. A drummer is a person who plays the drums.
In most popular music and jazz, drums or drummer usually refer to a drum kit.
In the past, drums were used as a means of communication.