You can think of the retina as the translator of light. Light enters your eye through the pupils and is focused by the lens. The focused image then goes to the retina, a thin layer of light-sensitive tissue that lines the back of your eye. The retina processes that light through photoreceptor cells that detect color and light-intensity and translates it into neural signals. The signals travel up the optic nerve to the brain, which decodes and interprets what you are looking at.