Markup formats have become the preferred method for producing high quality GUIs. Modern markup languages are modular and decouple content markup from presentation and layout markup. The specification against which content from authors and execution environments are developed is XML-based DTD or XSD. These specifications typically allow for extensions and accept plug-ins (e.g., embedding Flash using the <Object> tag) that essentially extend the capabilities of the markup language to provide a rich, powerful, interactive framework. |