Calluses can be annoying, but your body actually forms them to protect sensitive skin. Calluses and Corns are often confused with one another.
Calluses can develop on hands, feet , or anywhere there is repeated friction -- even on a violinist's chin. Like corns, calluses have several variants. The common callus usually occurs when there's been a lot of rubbing against the hands or feet. A plantar callus is found on the bottom of the foot.
Some callusses on the feet develop from an improper walking motion, but most are caused by ill-fitting shoes. High-heeled shoes are the worst offenders. They put pressure on the toes and make women four times as likely as men to have foot problems. Other risk factors for developing calluses include foot deformities and wearing shoes or sandals without socks, which can lead to increased friction on the feet.