over-easy is cooked on both sides but yolk is runny. Over-medium is less runny than over-easy,and over-hard is when both the yolk and white is cooked all the way through,

These terms refer to the egg, namely to its degree of cooked-ness: over-easy is cooked on both sides but yolk is runny; over-medium is less runny than over-easy, and over-hard is when both the yolk and white is cooked all the way through.