When you sit in front of a campfire, you are warmed by its heat. Hover your hand over a hot light bulb, and you'll feel the heat coming off it, even without touching it. Stand out in the sunshine, and you'll quickly get warmed by its rays. These examples illustrate our final mechanism of heat transfer, radiation. Radiation is when heat is transferred by electromagnetic waves, like radio waves, infrared waves, X-rays and even visible light!