There is only one file type that uses the .XAML extension:
Extensible Application Markup Language file that uses Windows Presentation Foundation (WPF) code; XAML (pronounced "zammel") is a descriptive programming language developed by Microsoft for creating user interfaces; introduced during the development stages of Longhorn, which is now Windows Vista.
XAML files are stored in a plain text format and can be viewed with a text editor. They are sometimes seen with a ".xoml" extension.
Updated: May 29, 2007