Class Trematoda: Infect the internal organs of hosts. Parasitic Can be endoparasites (live in the host) or ectoparasites (attach to external surfaces of the host. Size: ~ 1 cm to 10 cm Covered in an unciliated cuticle. Usually require 2 hosts to complete it's life cycle.
The difference between a mole and a wart is that moles are not contagious, but warts are. A mole, or nevus, is a collection of skin pigment cells. When they are small, they look like small brown dots. When the collection is larger, and slightly deeper, it can cause a raised skin colored bump over it.
The main differences between plantar warts and corns are in location, appearance and number. Planter warts mainly occur on the heel and the ball of the foot or the underside of the big toe. Corns usually occur between and on top of the toes but occasionally they can also appear on the ball and the heel.