A vision screening—the kind you’d get at a school, a DMV office, or a basic exam from a retail store, warehouse store, or big box store—checks whether you can see clearly at a distance. That’s useful, but limited. A comprehensive eye exam evaluates the full health of your eye, inside and out: the retina, optic nerve, cornea, lens, eye pressure, binocular coordination, peripheral vision, and more. Many serious conditions, including glaucoma and early macular degeneration, don’t affect your ability to read a letter chart until significant damage has already occurred. A screening won’t catch them. A comprehensive exam will.