The XML Binding Language (XBL) describes the ability to associate elements in a document with script, event handlers, CSS, and more complex content models, which can be stored in another document. This can be used to re-order and wrap content so that, for instance, simple HTML or XHTML markup can have complex CSS styles applied without requiring that the markup be polluted with multiple semantically neutral div elements.

It can also be used to implement new DOM interfaces, and, in conjunction with other specifications, enables arbitrary tag sets to be implemented as widgets. For example, XBL could be used to implement the form controls in XForms or HTML.

This practical guide provides you with the knowledge required to effectively use the XML Binding Language 2.0. It introduces both the basic and advanced concepts of XBL and describes its syntax and scenarios that should be considered best-practice. It also describes the purpose of the language elements described in the XBL 2.0 specification.

XBL describes the ability to associate elements in one document with script, event handlers, styles, and more complex content models in another document. You can use XBL to re-order and wrap content so that, for instance, simple HTML or XHTML markup can have complex CSS styles applied without requiring that the markup be polluted with multiple div elements. In addition, if you are a programmer, you can use XBL to implement new DOM interfaces, and, in conjunction with other specifications, it enables arbitrary XML tag sets to be treated as "widgets" (pluggable user interface components).