Have you ever wondered how your eyes are able to see? Well when you look at something, there are things in your eyes called cones and rods that help you see.

Cones		Cones are small nerve endings that, when you look at something, figure out how much red, green, and blue is in each part of what you are looking at. Why red, green, and blue? Because with those three colors, you can mix them in different ways to get any other color! Now the cones know the color of what you are looking at.
Rods		Rods are much like cones, but they have a different shape and instead of detecting color, they detect light and dark. They tell how much gray is in a picture. If you didn't have cones, you would see in black and white! When you "see" at night, since there is no color, you are seeing only shades of black and white. Without rods, when the light goes out you would be blinded!
The cones and rods make a great team. However, there are other parts of your eye that help out a lot!
Sclera		The sclera (pronounced "ska-le-ra") covers your eye and protects it. It is the white of the eye.
Cornea		The cornea is like the window of the eye. It is what you see through.
Iris		Your iris is the colored part of the eye. If you have blue eyes, you have blue irises.
Optic Nerve		The optic nerve transmits the image to the brain. The brain then understands what you are looking at.
Retina		The retina is the part along the back of the eye that changes the image to a message for your brain to interpret after the rods and cones have done their part.

The parts of the eye as described above are all labled on this image, except for the cones and the rods, which are part of the retina.