A drum is a musical instrument in the percussion group that can be large, technically classified as a membranophone. Drums consist of at least one membrane, called a drumhead or drum skin, that is stretched over a shell and struck, either directly with parts of a player's body, or with some sort of implement such as a drumstick, to produce sound. Drums are the world's oldest and most ubiquitous musical instruments, and the basic design has remained virtually unchanged for thousands of years. Most drums are called "untuned instruments" because they have no definite pitch, with the exception of a few such as timpani. Often, several drums are arranged together to create a drum set that can be played by a single musician.
