Keyboard instruments are played with the hands and can produce many notes at one time. They function well as both solo and accompaniment instruments because they can play both melodies and chords. Keyboard instruments produce sound from a variety of techniques borrowed from wind, string, and percussion instruments. The Organ produces sound by pumping air through pipes in response to keys pressed by the performer. The harpsichord produces sound using tiny devices called "plectrums" to pluck strings when the performer plays the keys. The piano uses hammers to strike strings in response to keys pressed by the performer. Click the Play button for a demonstration.