Glaucoma is a group of eye conditions that cause damage to the optic nerve, often due to increased pressure inside the eye (intraocular pressure). This damage can lead to gradual vision loss and, if left untreated, blindness. The most common form, primary open-angle glaucoma, develops slowly and painlessly, making it difficult to detect until significant vision loss has occurred. Other types, like angle-closure glaucoma, can cause a sudden increase in pressure, leading to severe pain and immediate vision problems. Glaucoma is usually managed through medications, laser treatments, or surgery to lower eye pressure and prevent further damage. Regular eye check-ups are essential for early detection, as the condition is often asymptomatic in its early stages.