Silverlight is a new web presentation technology that is created to run on a variety of platforms. It enables the creation of rich, visually stunning and interactive experiences that can run everywhere: within browsers and on multiple devices and desktop operating systems (such as the Apple Macintosh). In consistency with WPF (Windows Presentation Foundation), the presentation technology in Microsoft .NET Framework 3.0 (the Windows programming infrastructure), XAML (eXtensible Application Markup Language) is the foundation of the Silverlight presentation capability.
Silverlight is the next step in evolving the potential user-experience richness in which application developers and designers can present to their clients. It does this by allowing designers to express their creativity and save their work in a format that will work directly on the Web. In the past, a designer would design a Web site and a user experience using tools that provide a rich output, but the developer would have to meet the constraints of the Web platform in being able to deliver them.
In the Silverlight model, designers can build their desired user experience and express this as XAML. The XAML can then be incorporated directly by a developer into a Web page using the Silverlight runtime. Thus, the two can work more closely than ever before to provide a rich client user experience.