Keratoconjunctivitis sicca, commonly known as dry eye syndrome, is a condition where the eyes do not produce enough tears or the tears evaporate too quickly. This leads to dryness, irritation, and inflammation of the cornea and conjunctiva, the outer layers of the eye. Symptoms may include a gritty sensation, redness, and blurred vision. The condition can be caused by various factors, including aging, certain medications, and environmental conditions like wind or smoke. Treatment options often involve artificial tears, lifestyle changes, or medications to increase tear production, aiming to relieve discomfort and protect the eye's surface.