Original: Pythagorean tuning A Pythagorean tuning is technically a type of just intonation, in which the frequency ratios of the notes are all derived from the number ratio 3:2, a ratio of central importance to the School of Pythagoras in Ancient Greece.
Simplified: Pythagorean tuning, a type of just intonation in which the ratios of the frequencies between all notes are all multiples of 3:2.