 The XAML code is ultimately compiled into a managed assembly in the same way all .NET languages are, which means that the use of XAML for development does not incur a performance cost.Windows Communication Foundation (codenamed Indigo) is a new communication subsystem to enable applications, in one machine or across multiple machines connected by a network, to communicate.WCF programming model unifies Web Services, .NET Remoting, Distributed Transactions, and Message Queues into a single Service-oriented architecture model for distributed computing, where a server exposes a service via an interface, defined using XML, to which clients connect.