The new presentation subsystem in the next version of Windows, code-named "Longhorn," offers powerful new capabilities to developers. This new subsystem, code-named "Avalon," allows developers to take advantage of its capabilities through a language—Extensible Application Markup Language (code-named "XAML"), as well as through modern object-oriented programming languages such as C#. Because most applications written to Avalon will probably be a mix of XAML and programming code,
this article discusses XAML tags used to control page layout along with the procedural code written to respond to events.