Sure, here is an SEO friendly HTML answer for the question "What is WCF?":

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What is WCF?

Windows Communication Foundation (WCF) is a framework provided by Microsoft for building distributed applications. It is part of the .NET framework and allows developers to create services that can communicate with each other over various protocols such as HTTP, TCP, and MSMQ.

WCF provides a unified programming model for developing service-oriented applications, making it easier to build and consume services that are interoperable across different platforms and technologies.

With WCF, developers can create services that expose functionality to other applications, allowing for seamless communication and integration between different parts of a distributed system.

Overall, WCF is a powerful tool for building scalable and reliable distributed applications in the .NET environment.

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This HTML provides a concise and SEO-friendly explanation of what WCF is and its importance in building distributed applications. It includes relevant meta tags for search engine optimization.