Dry Eye Syndrome: This is a common condition that can cause eye pain, usually due to inadequate tear production or poor tear quality. It's often associated with symptoms like dryness, grittiness, and irritation.

Conjunctivitis: An inflammation or infection of the outer membrane of the eyeball and the inner eyelid, which can cause pain, redness, and discharge.
Blepharitis: Inflammation of the eyelids that can cause pain, redness, and swelling, often associated with itching and burning sensations.
Corneal Abrasion: A scratch on the surface of the eye that can be very painful and may cause sensitivity to light, tearing, and a feeling of something being in the eye.
Uveitis: Inflammation of the uvea, the middle layer of the eye, which can cause pain, sensitivity to light, and vision problems.

Acute Angle-Closure Glaucoma: A medical emergency that causes severe eye pain, headache, nausea, vomiting, and vision problems due to increased pressure in the eye.
Endophthalmitis: A severe inflammation of the interior of the eye, usually caused by infection, which can lead to vision loss if not promptly treated.
Orbital Cellulitis: An infection of the tissues surrounding the eye that can cause pain, swelling, and vision problems, potentially leading to serious complications if not treated.

Scleritis: A severe inflammation of the sclera (the white part of the eye), which can cause deep, boring pain and tenderness to the touch.
Keratitis: An inflammation of the cornea that can cause pain, redness, and vision problems, often due to infection.
Optic Neuritis: Inflammation of the optic nerve that can cause pain with eye movement, vision loss, and impaired color vision, often associated with multiple sclerosis.