In traditional guitar notation, the letters p, i, m, and a are used to refer to the fingers on the picking hand. Taken from the Spanish language, here’s what the letters represent:
p = pulgar (thumb)
i = indice (index or first finger)
m = medio (middle or second finger)
a = anular (ring or third finger)
You see a visual example of this Spanish fingering system in the following figure. Occasionally you come across pimac, where the letter c stands for chico, the pinky finger.
