Musical keyboard

A musical keyboard is the set of adjacent depressible levers or keys on a musical instrument. Keyboards typically contain keys for playing the twelve notes of the Western musical scale, with a combination of larger, longer keys and smaller, shorter keys that repeats at the interval of an octave. Depressing a key on the keyboard causes the instrument to produce sounds, either by mechanically striking a string or tine (piano, electric piano, clavichord); plucking a string (harpsichord); causing air to flow through a pipe (organ); or strike a bell (carillon). On electric and electronic keyboards, depressing a key connects a circuit (Hammond organ, digital piano, synthesizer). Since the most commonly encountered keyboard instrument is the piano, the keyboard layout is often referred to as the "piano keyboard".

The twelve notes of the Western musical scale are laid out with the lowest note on the left; The longer keys (for the seven "natural" notes of the C major scale: C, D, E, F, G, A, B) forward. Because these keys were traditionally covered in ivory they are often called the white notes or white keys. The keys for the remaining five notes—which are not part of the C major scale—(i.e.,C♯/D♭, D♯/E♭, F♯/G♭, G♯/A♭, A♯/B♭) (see Sharp and Flat) are raised and shorter. Because these keys receive less wear, they are often made of black colored wood and called the black notes or black keys. The pattern repeats at the interval of an octave.

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