What did Galileo discover when he dropped 2 cannon balls of different weights from the leaning tower of pisa

Hevier objects fall faster than light objects.

According to the traditional account, to refute the Aristotelian notion that heavier objects fall faster than light ones, Galileo performed an experiment from the top of the leaning tower of Pisa. He dropped two spheres of different weight and observed that both hit the ground at the same time.