eli5: in music, since there are 12 notes per octave, why are only 7 letters used instead of 12?

Question

eli5: in music, since there are 12 notes per octave, why are only 7 letters used instead of 12?

In: 15

Answer 1

Other people are doing fine answering this in a specific way. I’ll add that the big picture of music is a mish-mash of many labeling systems that were too simplistic to capture everything.