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.
Warts are small growths caused by a viral infection of the skin or mucous membrane. This virus infects the epidermis (surface) layer, and are contagious, easily passing from person to person. Warts can also pass from one body part to another. Common warts are hand warts, foot warts, and flat warts. Hand warts frown around the fingers (specifcally the nails) and on the backs of hands. They appears mostly in areas where the skin may be 'broken'.