What is the purpose of a fever?

When your body temperature rises because of an infection, it's called a fever. Fevers are caused by chemicals called pyrogens flowing in the bloodstream. Pyrogens make their way to the hypothalamus in the brain, which is in charge of regulating body temperature.

The purpose of a fever is that ur body is trying to fight off what ever is in ur body so in the process they use a fever to fight it off.