drum

A musical instrument consisting of a membrane of skin or plastic (rarely of other materials) stretched over a hollow resonator or frame, usually of wood or metal. Drums are normally played by striking the membrane with a stick or with the hands, and may be classified according to their shape (eg conical, cylindrical, ‘hourglass’, kettledrums) and whether they have a single membrane or are double-headed. The kettledrum is one of the few that can be tuned to a definite pitch. Drums are known from Neolithic times, and are found worldwide. Used for a variety of functions in civil and religious ritual, and for communication over distances (‘drum-languages’), their powers gave them a special (often sacred) place in early societies.

A "drum" is a musical instrument in the percussion family, 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. Other shapes include a frame design (tar), truncated cones (bongo drums), and joined truncated cones (talking drum).

Drums with cylindrical shells can be open at one end (as is the case with timbales), or can have two drum heads. Drums with two heads covering both ends of a cylindrical shell often have a small hole somewhat halfway between the two drumheads; Exceptions include the African slit drum, made from a hollowed-out tree trunk, and the Caribbean steel drum, made from a metal barrel. Drums with two heads can also have a set of snares held across the bottom head, top head, or both heads, hence the name snare drum.

On modern band and orchestral drums, the drumhead is affixed to a hoop (also called a "rim"), which in turn is held onto the shell by a "counterhoop", which is then held by means of a number of tuning screws called "tension rods" (also known as lugs) placed regularly around the circumference. The sound of a drum depends on several variables, including shape, size and thickness of its shell, materials from which the shell was made, type of drumhead used and tension applied to it, position of the drum, location, and a manner in which it is struck.

Within the realm of popular music and jazz, "drums" usually refers to a drum kit or a set of drums, and "drummer" to the actual band member or person who plays them. Many drummers are also adept at playing both the drum set and a set of hand drums for added musical variety. The talking drums of Africa can imitate the inflections and pitch variations of a spoken language and are used for communicating over great distances.- see drum (communication). In Sri Lankan history drums were used for communication between the state and the community, Sri Lanka drums have a history running back 2500 years.