Microsoft Windows Server 2008 R2 Standard and Enterprise

Web Application Platform
Virtualization with Hyper-V
Scalable and Reliable
Easy to Manage
Better Together with Windows 7
Expanding existing technology and adding features to enable IT professionals to increase the reliability and flexibility of their server infrastructures
It helps save time, reduce costs, and provide a platform for a dynamic and efficiently managed data center
It is the most robust, secure, and reliable foundation on which to develop, deliver, and manage rich user experiences and applications.