Firstly, a corn is a type of common wart, and it actually has clear differences from a callus. Common warts generally occur on the soles of the feet, or on the proliferative protruding surface, typically characterized by specific manifestations. In such cases, there usually are also prominent manifestations, and these conditions can also cause some minor pain.

On the other hand, calluses are completely the opposite of corns. The surface of a callus is generally not protruding, meaning the skin is flat and usually quite smooth. In this respect, there is a fundamental difference on the surface. Moreover, calluses can potentially be caused by local compression factors.

As for corns, they are usually caused by lowered immunity. That is, viral infections are what lead to the problem of corns.