What are they?:
Simply put, a gong is a metallic musical instrument that is played by striking with a mallet. There are two main types of gongs. The suspended gong is generally a flat sheet of metal (bronze, typically) that is hung in the air vertically. It is not tuned to a specific pitch, and thus makes a loud, multi-toned "crash" when played. The bossed or button gong is common in gamelan ensembles, among other places. Button gongs have a raised center point and are tuned to a specific note. They are usually played horizontally. Gongs can range in size from just a few inches to several feet in diameter.
Where do they come from?:
Gongs are traditionally found throughout East and Southeast Asia, most prominently in China and throughout Indonesia.
The significance of the gong:
Gongs are used both for religious ceremonial purposes and for making music throughout Asia. They play an important role in the aforementioned gamelan orchestra, as well as Chinese opera, and they are commonly used in Taoist and Buddhist Meditation, among other religions, and gongs are used to call the Gods in some animist tradditions. Some cultures believe that the instruments themselves harbor spirits. Gongs also serve a practical purpose, and are used to sound arrivals, signal celebrations, call people to gather, mark certain hours of a day, and myriad other occasions in which a loud noise could prove useful.
The most common type of gong, from a Western perspective, is the loud, crashing Chinese tam-tam or chau gong. The tam-tam is a standard part of the percussion section of a Western classical symphony orchestra, and is also well-known to game show fans from the Chuck Barris-hosted program The Gong Show. The gong has been used as a sound effect and a musical element in a number of movies, TV shows, and musical recordings, as well.