The abbreviations, numbers, and plus (+) or minus (-) signs on your eye prescription have different meanings depending on how well you see. They can also change as you age. Here’s what they mean. The ...

Positive numbers on an eye prescription indicate they are correcting farsightedness, while negative numbers correct shortsightedness. A larger number suggests a stronger prescription. Although roughly ...

An optical illusion is a visual phenomenon where the brain perceives an image differently from reality. It occurs when the information sent from the eyes to the brain is misinterpreted, leading to a ...