Microsoft’s Silverlight technology, like Flash, allows you to create interactive content that runs on the client, with support dynamic graphic, media and animation. Silverlight is deployed using a lightweight browser plug-in and supports a wide range of different browsers and operating systems. Silverlight is based on as scaled-down version of .NET’s common language runtime (CLR) and thus allows developers to write client-side code using pure C# or VB.NET.

Silverlight exists in several versions. The first version, Silverlight 1 included the 2D drawing features and the media playback features, but it didn’t include the CLR engine or support for .NET languages, and developers were forced to use JavaScript. The second version, Silverlight 2, added the .NET-powered features. It introduced a scaled-down CLR, a subset of .NET Framework classes, and a user interface based on Windows Presentation Foundation (WPF), which desktop developers use to build cutting-edge Windows applications.The versions that have followed—Silverlight 3 and Silverlight 4—keep the same underlying infrastructure and simply add more features.