The figure below shows the labeled diagram of the human eye. The main parts of eye are-
Cornea, Iris, Pupil, Ciliary muscles, Eye lens, retina and optical nerves which are labeled in the diagram below.

Image Formation: The light rays coming from object enter through cornea of eye, pass through the pupil of the eye and fall on the eye lens. The eye lens is a convex lens, so it produces real and inverted image of object.

The optical nerve conveys the image formed on retina to brain and we get sensation of vision.