Corns and calluses form on the skin because of repeated pressure or friction. A corn is a small, tender area of thickened skin that occurs on the top or side of a toe. A callus is a rough, thickened area of skin that appears because of repeated irritation or pressure to an area of skin. Calluses usually develop on the palms of the hand and soles of the feet.
Update Date 4/13/2015
Updated by: Dennis Ogiela, MD, Orthopedic Surgery and Physical Medicine and Rehabilitation, Danbury Hospital, Danbury, CT. Review provided by VeriMed Healthcare Network. Also reviewed by David Zieve, MD, MHA, Isla Ogilvie, PhD, and the A.D.A.M. Editorial team.