The distance between two pitches having the same name is called an octave. If you play successive pitches on the white keys of a piano, there comes a point at which the pitch seems to duplicate an earlier pitch. The two pitches are said to be an octave apart. Notice that the pitches will have the same letter name (as learned in the section about the piano keyboard). Men and women instinctively sing an octave (or possibly two octaves) apart.