XBAP

This document explores the potential of Windows Presentation Foundation on the Web. In addition, it discusses the technologies behind Web Browser Applications as well as how one might migrate their existing sites.

http://msdn.microsoft.com/en-us/library/aa480223.aspx

Comparing WPF applications and XBAP – What’s the difference?

Comparing WPF applications and XBAP – What’s the difference here is good link