Girl With A Musical Instrument

User interfaces
Regardless of how the sound in an instrument is produced, many musical instruments have a keyboard as the user-interface. Keyboard instruments are any instruments that are played with a musical keyboard. Every key generates one or more sounds; most keyboard instruments have extra means (pedals for a piano, stops for an organ) to manipulate these sounds. They may produce sound by wind being fanned (organ) or pumped (accordion), vibrating strings either hammered (piano) or plucked (harpsichord), by electronic means (synthesizer), or in some other way. Sometimes, instruments that do not usually have a keyboard, such as the glockenspiel, are fitted with one. Though they have no moving parts and are struck by mallets held in the player's hands, they have the same physical arrangement of keys and produce soundwaves in a similar manner.