A bell plate is a percussion instrument consisting of a flat and fairly thick sheet of metal, producing a sound similar to a bell. They are most often used in orchestral and theater music.

An idiophone is any musical instrument that creates sound primarily by the vibration of the instrument itself, without the use of air flow, strings (chordophones), membranes (membranophones) or electricity (electrophones). It is the first of the four main divisions in the original Hornbostel–Sach system of musical instrument classification. The early classification of Victor-Charles Mahillon called this group of instruments autophones. The most common are struck idiophones, or concussion idiophones, which are made to vibrate by being struck, either directly with a stick or hand or indirectly, with scraping or shaking motions. Various types of bells fall into both categories. A common plucked idiophone is the Jew's harp.