You l~arn about the world through your senses. Mostly<br >you learn about it through your eyes. But seeing takes more<br >than a pair of eyes. It also takes a brain， which works with the<br >eyes. Your eyes send messages to your brain. The brain makes<br >sense of the messages. Then， and only then， do you see what<br >you see.<br > Your brain and eyes are the parts of your body that make<br >seeing possible. But in order to see， there is still something<br >else you need--light. Everything you look at is seen with<br >light. Without light you see nothing.<br > Light is one kind of radiation. It is given off， or radiated，<br >by the sun and stars， by fire， by lamps. Anything that radiates<br >light is called a source of light.<br > A tiny firefly is a source of light， but the moon， no matter<br >how bright， is not. A firefly makes its own light. The moon<br >does not. It shines because the sun s light is bouncing off it， or<br >being reflected.<br > People， plants， and houses do not usually shine， but they<br >do reflect light. That is why you see them. Rays of light<br >bounce off them and reach your eyes.<br > But that is only a small part of the story. To find out more<br >about how you see what you see， use your eyes and brain to<br >read on， in a good light.<br >