A gong (Javanese: gong) is an East and South East Asian musical percussion instrument that takes the form of a flat metal disc which is hit with a mallet.
Gongs are broadly of three types. Suspended gongs are more or less flat, circular discs of metal suspended vertically by means of a cord passed through holes near to the top rim. Bossed or nipple gongs have a raised centre boss and are often suspended and played horizontally. Bowl gongs are bowl-shaped, and rest on cushions and belong more to bells than gongs. Gongs are made mainly from bronze or brass but there are many other alloys in use.
Gongs produce two distinct types of sound. A gong with a substantially flat surface vibrates in multiple modes, giving a "crash" rather than a tuned note. This category of gong is sometimes called a tam-tam to distinguish it from the bossed gongs that give a tuned note. In Indonesian gamelan ensembles, some bossed gongs are deliberately made to generate in addition a beat note in the range from about 1 to 5 Hz. The use of the term "gong" for both these types of instrument is common.