DHTML (Dynamic HyperText Markup Language)
DHTML describes the useage of several technologies (HTML, JavaScript, CSS, and the DOM) for creating web pages that react to user events, most typically for interactive purposes and animation.
DHTML is extremely useful for changing or tailoring the content or user functionality of a page or site based on the specific users' needs or interests. DHTML allows for dynamic customizability to be built into otherwise static pages and, prior to DHTML, such capability was reserved for sites built using server side coding such as ASP & PHP.