1. Conjunctiva
This is the transparent covering of the eye that lies between the eyelid and the front of the eye.

2. Cornea
This is the window of the eye where the majority of focus takes place.

3. Iris
Actually classified as a muscle, the iris is the colored portion of the eye that adjusts the amount of light allowed to enter into the pupil.

4. Pupil
This is the black spot in the center of the eye where light enters. Pupil size changes when the iris tenses or relaxes depending on the amount of light present.

5. Lens
Located behind the pupil, the lens is the secondary mechanism of focus after the cornea, adjusting the amount of refraction required within the eye to focus an object on the retina.

6. Retina
The retina is the nerve center of the eye where light is converted into an electrical signal that travels to the brain. Cells, called rods and cones, within the retina transmit these signals along the optic nerve, consequently enabling sight.

7. Optic Nerve
This is the pathway between the eye and the brain along which the signals produced by the rods and cones travel to the brain.