A wart is one of the soft tissue disorders that exist on the foot. They're sometimes mistaken for calluses. Children, particularly adolescents, appear to be more vulnerable to warts than adults, which is likely attributed to a poorly evolved immune system. Warts also surface with very tiny black spots.
The virus is found in wet, humid conditions such as swimming pools and showers, and causes warts, which normally invade the skin by tiny or unseen cuts and abrasions. Plantar warts are also acquired when walking barefoot on the areas where the virus is present.