Have you ever wondered why overheating on a hot day and getting a fever when you're sick feel so different? Both involve an increase in your body's temperature. However, in one case your brain and body do everything they can to cool you off, while in the other they push the temperature inside your body to extreme levels. This video describes these two responses in detail and takes some of the mystery out of fever.

This video is available in both English and Spanish with closed captions.