Silverlight is Microsoft's cross-browser, cross-platform, and cross-device technology for delivering the next generation of .NET based media experiences and rich interactive applications for the Web.

Microsoft Silverlight is a free framework empowering the developer to build new types of applications for the Web regardless of target platform or browser, using all the familiar features, languages and tools of the .NET framework.

It is considered to be the future of web development and design and is highly promoted by Microsoft. Microsoft itself is converting all its existing web sites to Silverlight.

Microsoft has developed Silverlight based on their experience with ASP.NET AJAX. In a way, Silverlight extends the features and functionality of AJAX to develop and design cutting-edge web solutions with never-looked-before design.

We have been developing Silverlight Applications since its first launch. It's based on Xaml (eXtensible Application Markup Language), which was introduced with .NET 3.0 for WPF (Windows Presentation Foundation). We had already been using Xaml for WPF Applications, and that made learning Silverlight easier for us.

Silverlight is still an evolving technology, but we have already developed a couple of large Silverlight Applications, including data-driven applications using WCF Data Services.