An idiophone is a musical instrument that produces sound primarily by the vibration of the instrument itself, without the use of air flow, strings, membranes, or electricity. The vibration of a resonant solid material, such as wood, metal, or stone, produces the initial sound. There are eight basic types of idiophones: concussion, friction, percussion, plucked, scraped, shaken, stamped, and stamping. The most common type of idiophone is the struck idiophone, which includes instruments like the wood block, singing bowl, steel tongue drum, triangle, and marimba. Other examples of idiophones include bells, rattles, and the Jews harp. The names idiophone and membranophone replace the looser term percussion instruments when a precise, acoustically based classification is required.