Microsoft Hyper-V

Tip - Microsoft Hyper-V, codenamed Viridian and formerly known as Windows Server Virtualization, is a hypervisor-based virtualization system for x86, x64 systems.

Details - Microsoft® Hyper-V™ Server 2008 R2 is a stand-alone product that provides a reliable and optimized virtualization solution enabling organizations to improve server utilization and reduce costs. Since Hyper-V Server is a dedicated stand-alone product, which contains only the Windows Hypervisor, Windows Server driver model and virtualization components, it provides a small footprint and minimal overhead.

Reference -  

http://www.microsoft.com/hyper-v-server/en/us/default.aspx

Posted by - Aneesh Valeri