This educational guide explains glaucoma as a progressive eye disease where increased pressure inside the eye damages the optic nerve, leading to irreversible vision loss and eventual blindness. Glaucoma typically has no early symptoms, making regular eye exams essential—especially for people over 30, those with a family history of glaucoma, diabetes, high blood pressure, or prior eye injuries. The document emphasizes that while surgery can help prevent further vision loss, it cannot restore vision already lost. Early detection and timely surgery by a trained eye doctor are key to preserving sight.