Learn in the textbookFeedback Display and Web Design Implementation
DefinitionA rollover (ロールオーバー) is an effect in which an element's color, image, or other aspect of its look switches when the pointer moves over it.
ExplanationNormally the original look comes back when the pointer moves away, and the effect is made by swapping an image or changing a color. The change lets users confirm, before pressing, that the element can be pressed and which one they are pointing at now.
AnalogyIt works like a porch light that turns on when someone approaches and goes off when they leave.
Memory hookRoll over means to roll across the top of something. Picture the image flipping to a new face each time the pointer rolls across the element.