Silverlight
Silverlight (link to silverlight.net) brings Rich User Experience to the Web. It is a plugin for popular web browsers (IE, Firefox, Safari) and also available for Linux Browsers.
Silverlight does not require Windows Server, it can be hosted in Linux + Apache environment.
If you require Rich User Experience on the Web, Silverlight is the answer.
WPF
Windows Presentation Foundation (WPF) brings Rich User Experience to the PCs. It is a comprehensive framework for modern desktop applications.
WPF requires Windows + .NET Framework 3.0 to be installed in the PCs, thus if you require Rich User Experience on the PC, WPF is the answer.
WinForms
Windows Forms (WinForms) is the older version of WPF. It is suitable for organization that has not upgraded to faster PCs and Windows Vista.
If you require Rich User Experience on Windows XP and Non-Dual-Core PCs, WinForms is the answer.
ASP.NET
ASP.NET allows Database-Driven Web Applications to be easily developed and maintained. It is a comprehensive framework for Server-Side Development.
ASP.NET requires Windows Server for hosting and supports any Web Browser without installing plugin.
If you require Database-Driven Web Applications supporting Desktop Web Browser and Mobile Web Browser, ASP.NET is the answer.
Windows Mobile
Windows Mobile brings Rich User Experience to hand-held devices. It brings the best of desktop technologies into handheld devices such as Mobile Phones and PDAs.
Windows Mobile requires Windows Mobile-powered devices. For a list of devices, see microsoft.com/windowsmobile.
If you require the familiarity of Desktop Applications, but needs to be mobile, Windows Mobile is the answer.
