Platyhelminthes are seperated into Turbellaria, which are non-parasitic creatures.
Flatworms are mainly predators living in water or dark, humid areas.
The most common type of flatworm is the Tapeworm. The tapeworm is a parasitic flatworm, the only parasitic Platyhelminthes.
3 different Classes;
1) Terbullarians (Planarians)
2) Trematoda (Flukes)
3) Cestoda (Tapeworms)
1) Cilia, which help them glide along the floor.
2)Muscle Cells, which help them twist.
Other parasitic platyhelmenthes feast on blood.
And some platyhelmenthes don't eat, but absorb nutrients directly.