"Atypical moles" (also referred to as Clark's nevi or dysplastic nevi) are moles that are considered to be precancerous or more likely to turn into melanoma than regular moles. When looking at an atypical mole on the skin, one will see some of the features that one sees when looking at melanoma such as: an irregular border, slight variation in color, or asymmetry (if you cut the mole in half, the two halves do not look the same). When a pathologist looks at an atypical mole under the microscope, it has features that are in-between a normal mole and a melanoma. Most experts believe that atypical moles are at higher risk of turning into melanoma as compared to normal moles. Melanoma is a deadly form of skin cancer which kills quickly if not removed in time.