There is only one type of skin that wraps your body. The skin on
your feet are not different. However, feet usually a callus (or
callosity) is an especially toughened area of skin which has become
relatively thick and hard in response to repeated friction,
pressure, or other irritation. Rubbing that is too frequent or
forceful will cause blisters rather than allow calluses to form.
That is usually what protect the soles of your feet.