Floaters retain this name due to the fact that many people notice dark dots, lines or particles in their vision that move around as though floating in the eye. Floaters cast shadows on the retina, the light-sensitive tissue lining the back of the eye. The retina then sends visual signals to the brain, resulting in an image.
Floaters come and go with eye movements, such as blinking.
They follow eye movements, but lag behind and float to a halt a few seconds after the eyes stop moving. These images are most obviously appear when looking at a bright, uniform field of vision, such as a white wall or a clear sky. People may experience one or several floaters in one eye or both. Floaters are not the same as the spots you see after looking at intense light such as from a flashbulb. Most people see floaters some time during their lives.