The innermost layer of the eye made of think, delicate and transparent membrane is called retina. It has three regions - optic disc, macula lutea and peripheral retina. The retina has several layers including the layer of special cells called photoreceptors (rod cells and cone cells). Rod cells help with motion detection and low light vision along with black-white visuals. The photoreceptor cells called as cone cells are mainly concentrated in a small area on retina called as macula. A small depression called fovea centralis is found in the macula region which is concentrated with only cone cells. This section of retina is responsible for maximum visual acuity and color vision.