Pronation is foot in motion, from foot-strike on the outside of the heel through the inward roll of the foot. It occurs as the foot rolls from the outer edge to the inner edge. Pronation is considered an important and healthy response to the intense amount of shock imposed upon the foot and is integral to propelling you forward. If the foot pronates too much or too little and does so frequently, it may result in a decrease in performance and increase the possibility of injury.
The different type of Pronations and how to identify them.
If the shoes have a slight or significant inward tilt as they go from heel strike to toe off, then you exhibit an over-pronation.
If the shoes appear to be neutral and do not tilt inward nor out, then you exhibit a pronation-neutral/ normal.
If the shoes have a slight or significant outward tilt, then you exhibit an under-pronation (supination)
One easy way to see which category you belong to is to check the wear and tear of the sole in your old pair of shoes.