This is a fundus of the eye. In short, this is how the interior of the back of the eye looks to the eye of the person using a fundoscope (Also known as Ophtalmoscope). The Red lines are blood vessels, the clear spot where the blood vessels seem to emerge is the BLIND spot or OPTIC DISC. This area has NO photoreceptors (Cells allowing us to see)

Another less visible area is called the MACULA Lutea. The macula lutea is the complete opposite of the Optic Disc. It is an area of great concentration of CONES. Since the cones are responsible to daytime vision (COLOR VISION), the macula lutea is very important in vision. This is the area where teh things our eyes focus on are projected.
 
Imagine now that the macula lutea is damaged. This leads to a condition called MACULAR DEGENERATION. The subject CANNOT see what he/she is focusing on.