Definition: XUL

(EXtensible User Interface Language) A set of XML tags for describing graphical user interfaces. Designed for cross-platform porting and derived from the Mozilla open source project, XUL supports the following Web functions: cascading style sheets (CSS) for styles, JavaScript for event handling, the XML Binding Language (XBL) for creating reusable widgets and the Resource Description Language (RDF) for storing dynamic content. XUL also supports well-formed HTML code.