What is User Interface Markup Language?

A user interface markup language (UIML), a markup language extension of XML that describes graphical user interfaces and controls. It promotes the creation of web pages that can be viewed on any kind of interface devices, right from the large screen desktops to the small screen smart phones or PDAs. One of the most interesting things about UML is that web content can be created once without knowing specifically on which devices it will be viewed on. Programmers use UIML style sheets to describe elements of the user interface such as menus, boxes and input buttons to get the content respond to different devices. A given UIML file also specifies the content such as text, names of images, etc. in those fields or elements. In addition to this, UIML allows developers to describe possible user input events and resulting actions. The markup is organized in the UIML specification, which also involves the formal XML document type definition (DTD) for UIML.