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.
Warts are generally caused by a human virus known as papilloma while moles are generally related with age and caused by hormones and environmental factors. There are cases when kids are born with moles but in general moles on the face increase with increase in age.
Not skin tag: Hpv, or human papilloma virus, causes warts, including common warts and genital warts. These are different from skin tags. A skin tag is generally a flap of skin or similar, while a wart is flat. Because warts contain virus, they can be infectious.