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A callus is an area of thickened skin that forms as a response to repeated friction, pressure, or other irritation. Since repeated contact is required, calluses are most often found on feet because of frequent walking and incorrectly fitting footwear. While they can be perceived as being unsightly, calluses are generally not harmful, but if neglected for long periods may sometimes lead to other problems, such as a skin ulceration or infection, or cause the sufferer to try and offload the affected painful area, which can place excessive stress on the asymptomatic side. Rubbing that is too frequent or forceful will cause blisters as opposed to calluses to form.

why do i have callus on my hands