A drum is a percussion instrument consisting of a membrane stretched taut over a hollow space. When the membrane or skin is struck with the hand or another object such as a stick, a percussive sound is produced. Drums are used in almost all forms of music to keep the rhythm and sometimes to mark important or dramatic moments. Drums are among the oldest musical instruments.
Drums come in a wide variety of sizes, shapes, and varieties. The biggest is the bass drum. Other commonly used drums include the snare drum, which has snares stretched across the skin, the tom-tom, and the tabla, which is used in Indian music.
In pop, rock, and jazz, several drums are usually arranged in a drum kit, along with cymbals and sometimes bells and other percussion instruments. These can then be played by a single drummer. In heavy metal music particularly, drum kits can reach incredible sizes, often including a second bass drum (allowing for a very dramatic bass drumroll), numerous tom toms and upwards of half a dozen cymbals. At the other end of the scale, Reni from the Stone Roses was respected for drumming very effectively with a basic, almost minimalist kit.