BOX- This is the little box that appears when you place your mouse over a graphic or a link. This little box usually includes text describing the graphic or link. The mouse-over is generated by an ALT Tag (for graphics) or a Link Title Tag (for links).
A word or image that changes when a cursor is moved across it.
When you use your mouse to move the screen cursor over some elements of the web site creation tool, a pop-up menu or some other graphical element appears. This effect is called mouse-over.