Microwaves are a form of radiation. They can pass through things that would block ordinary radio waves, such as rain and fog. Microwaves can also be focused and sent in a narrow beam, making them very useful for transmitting radio messages over long distances. Microwaves are widely used to transmit television signals to and from orbiting satellites in space, and they are also the basis on which modern mobile telephones work.
In radar, a beam of microwave energy scans the target area and bounces back signals, producing a picture of the object. Microwaves penetrate the food in a microwave oven, causing the molecules to move about very rapidly. This rapid movement generates the heat that cooks the food.
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