mouseover

A mouseover (mouse hover or hover box) is a graphical control element that is activated when the user moves or ‘hovers’ the pointer over its trigger area, usually with a mouse.

When your mouse passes over the HTML code containing the mouseover element, it signals the JavaScript event to take place. Mouseovers are widely used in Navigation Bars, pop-up windows, and/or form submissions.

For example, on the screenshot below please see the menu element that changes its color when the mouse is put over it: