The Xen Project hypervisor is an open-source type-1 or bare-metal hypervisor, enabling multiple instances of operating systems, or different operating systems, to run in parallel on a single physical machine (or host). It is the only open-source type-1 hypervisor available and serves as the foundation for numerous commercial and open-source applications, including server virtualization, Infrastructure as a Service (IaaS), desktop virtualization, security applications, and embedded or hardware appliances. The Xen Project hypervisor powers the largest cloud deployments in production today.