Microsoft Silverlight is a cross-platform, cross-browser, and cross-device plug-in for delivering the next generation of media experiences and rich interactive applications for the Web. Now with new mobile device focused implementations of Silverlight, developers and designers can easily take existing code, assets, skills, and tools and deliver superior user experiences on mobile devices. With initial support for Windows Mobile and Nokia S60 (including any S60 based handset) mobile operating systems Silverlight provides broad reach into the mobile space.
Microsoft Silverlight is in the Other Browser Add-ons & Plug-ins category of the Browsers section.