A gong is a percussion instrument, usually with a definite pitch. It consists of a large metal plate (usually circular) which is hung on a stand and beaten with some kind of mallet (usually covered with felt or leather). Gongs are found all over the world and are of ancient origin. The earliest type consisted of a flat bronze plate, but later examples have a curved surfaced or a raised central boss. In Asian countries it is customary to have a whole set of gongs hung as a chime, either vertically on a frame or horizontally in a wooden trough (as in Javanese gamelan).
Gongs are often confused with the tam-tam, an instrument of indefinite pitch which has been used in the orchestra since about the end of the 19th century. They vary in size from about 51cm to 71cm in diameter.