Eyes

"The eye is the organ of sight (vision) in humans and animals. The eye works by transforming light waves into visual images. Eighty percent of all information received by the human brain comes from the eyes. Eye color is created by the amount and type of pigment in the iris. Multiple genes inherited from each parent determine a person’s eye color. The eye is a slightly asymmetrical globe, about an inch in diameter. The front part of the eye (the part you see in the mirror) includes:
• The iris (the pigmented part)
• The cornea (a clear dome over the iris)
• The pupil (the black circular opening in the iris that lets light in)
• The sclera (the white part)
• The conjunctiva (an invisible, clear layer of tissue covering the front of the eye, except the cornea)"

Stye

A sty (sometimes spelled stye) is a tender, painful red bump located at the base of an eyelash or under or inside the eyelid. A sty results from a localized infection of the glands or a hair follicle of the eyelid. The medical term for a sty is hordeolum (plural, hordeola). A stye is caused by bacteria from the skin that get into the oil glands in the eyelids that provide lubrication to the tear film. Styes a lot like common acne pimples that occur elsewhere on the skin. You may have more than one stye at the same time.