![493px-DotNet3_0_svg[5]](http://www.aygfsteel.com/images/blogjava_net/wujun/WindowsLiveWriter/net3.0_1342A/493px-DotNet3_0_svg%5B5%5D_thumb.png)
WCF is a new communication subsystem to enable applications, in one machine or across multiple machines connected by a network, to communicate.
WPF is the graphical subsystem feature of the .NET Framework 3.0 and is directly related to XAML.
WCS is a framework developed by Microsoft which securely stores digital identities of a person, and provides a unified interface for choosing the identity for a particular transaction, such as logging in to a website.
WWF is a Microsoft technology for defining, executing, and managing workflows.