The piano is a keyboard instrument that produces sound when the keys are
pressed. Most pianos have a row of 88 black and white keys: 52 white
keys for the notes of the C major scale (C, D, E, F, G, A, and B) and 36
shorter and thinner black keys raised above the white keys and set
further back, for sharps and flats. This means that the piano can play
88 different pitches (or "notes"), spanning a range of a bit over seven
octaves. The black keys are for the "accidentals" (F♯/G♭, G♯/A♭, A♯/B♭,
C♯/D♭, and D♯/E♭), which are needed to play in all twelve keys.
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