There are 88 keys on a piano. Some keys are called natural keys and others are called accidental keys, the white piano keys are called natural notes because they make a natural note when pressed on. Black piano keys are called accidental notes because they make a flat or sharp note when pressed on. The 7 natural notes are, C,D,E,F,G,A,B. The accidental notes are 5 per octave, they can be either flat or sharp. Learn about the two clefs where your left and right hands play. Treble clef and the Bass clef.