Silver light 4 is the latest iteration of Microsoft's cross-browser technology for creating rich user experiences on the Web. Like its predecessor, Silver light 3, it rides atop the .NET framework for maximum ease of use and coding efficiency. The new technology carries forward much of the work that has been done before and augments it in many important respects, including support for H.264 video, major improvements to the graphics engine (including true 3D rendering), and much richer data-binding options for interfacing with other applications.