Xen /ˈzɛn/ is a Hypervisor providing services that allow multiple computer operating systems to execute on the same computer hardware concurrently.
The University of Cambridge Computer Laboratory developed the first versions of Xen. The Xen community develops and maintains Xen as free software, licensed under the GNU General Public License (GPLv2). Xen is currently available for the IA-32, x86-64 and ARM computer architectures.
Read more about Xen: Architecture, History, Uses, Hosts, Xen Management Consoles, Commercial Versions of Xen