A feature of HTML that gives both Web site developers and users more control over how Web pages are displayed. With CSS, designers and users can create style sheets that define how different elements, such as headers and links, appear. These style sheets can then be applied to any page on a particular Web site. So in theory all the pages can be formatted the same way making it much easier. The term cascading derives from the fact that multiple style sheets can be applied to the same Web page. CSS was developed by the W3C.