Triangle (musical instrument)

The triangle is a musical instrument in the percussion family, and is classified as an idiophone in the Hornbostel-Sachs classification system. Triangles are made from a variety of metals including aluminum, beryllium copper, brass, bronze, iron, and steel. The metal is bent into a triangle shape with one open end. The instrument is usually held by a loop of some form of thread or wire at the top curve. The triangle theoretically has indefinite pitch, and produces a plurality of overtones when struck with an appropriate beater. The triangle has a triangular shape, which is why it is named a "triangle".