How does an earthworm differ from a roundworm?

Roundworms can cause serious damage to humans and other living things. Roundworms also live in pigs, so when people eat it pork undercooked, they can have roundworms inside their body, where it causes a disease. Earthworms cannot do any of these things that roundworms can do.

(Roundworms are parasites, so if you don't want to have parasites inside your body organs, DON'T EAT UNDERCOOKED PORK OR ANY TYPE OF MEAT)