Features of Silverlight:
For more information, see Layout, Input, and Printing, Graphics, Animation, and Media, and Controls.
Cross-browser, cross-platform support. Silverlight runs the same on all popular browsers (and on popular platforms). You can design and develop your application without having to worry about which browser or platform your users have. For more information, see Supported Operating Systems and Browsers.
Access to the .NET Framework programming model. You can create Silverlight applications using dynamic languages such as IronPython as well as languages such as C# and Visual Basic.
For more information, see Managed API for Silverlight Tools Support. You can use development tools, such as Visual Studio and Expression Blend, to quickly create Silverlight applications. For more information, see Silverlight Designer for Visual Studio 2010 and Expression Blend.
Networking support. Silverlight includes support for HTTP over TCP. You can connect to WCF, SOAP, or ASP.NET AJAX services and receive XML, JSON, or RSS data. For more information, see Networking and Web Services. In addition, you can build multicast clients with Silverlight. For more information, see Working with Multicast.
LINQ. Silverlight includes language-integrated query (LINQ), which enables you to program data access using intuitive native syntax and strongly typed objects in .NET Framework languages. For more information, see XML Data.