Navigator 2.0, Internet Explorer 3.0
<A onMouseOver="handler-statements"> a definition of the handler <AREA onMouseOver="handler-statements"> another definition; Navigator 3.0 only link.onmouseover a reference to the handler link.onmouseover(); an explicit invocation of the handler
By default, the browser displays the URL that a hypertext link refers to in the status line whenever the mouse goes over the link. The onmouseover() event handler is invoked before the URL is displayed. If the handler returns true, then the browser will not display the URL. Thus, an event-handler function that returns true can display a custom message in the status line by setting the Window.status property to any desired value itself.
Note that while this event handler returns true to tell the browser not to perform its default action (displaying the URL of a link), the onclick() event handler of the Link object must return false to tell the browser not to take its default action (following the link). This incompatibility exists for historical reasons. The standard for Form and form element event handlers is to return false to prevent the browser from performing a default action.