Silverlight is a cross-browser, cross-platform application framework for building rich internet applications (RIAs). It uses XAML for the user interface and .NET languages for coding. The UI, code, and resources are compiled into a .NET assembly and compressed into an XAP file, which is downloaded by the browser and run using the Silverlight plugin. Silverlight 5 is currently in beta with improvements to media, graphics, and application development capabilities. Visual Studio and Expression Studio are used for developing and designing Silverlight applications.