WINDOWS COMMUNICATION FOUNDATION (WCF) is the unified programming
model for writing distributed applications on the Microsoft platform.
It subsumes the prior technologies of ASMX, .NET Remoting,
DCOM, and MSMQ and provides an extensible API to meet a wide variety
of distributed computing requirements. Prior to WCF, you needed to master
each of those technologies to select the right approach for a particular
distributed application requirement. WCF simplifies this considerably by
providing a unified approach.