The Rollover Effect

One of the most common DHTML elements in Web pages is the rollover effect. When the user points to a button on a Web page, that button changes color or format. By highlighting a button this way, you help show the user that the button is being pointed to and that a mouse click will activate that button.

In the days before DHTML, when a user clicked a button, the click sent a message back to the Web page's server to fetch another page or part of a page. The user had to wait for this to occur.

Buttons that appear on Web pages often have graphic images on them. The graphic image may have the button's text and color and a design of some kind. DHTML scriptlets handle the rollover effect by changing the picture on the button to another ...

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