Virtualization allows multiple operating system instances to run concurrently on a single computer. Each virtual server acts like a unique physical device, capable of running its own operating system (OS).
It is a means of separating hardware from a single operating system. Each "guest" OS is managed by a Virtual Machine Monitor (VMM), also known as a hypervisor. Because the virtualization system sits between the guest and the hardware.
One physical machine to support multiple virtual machines that run in parallel.
It can control the guests' use of CPU, memory, and storage.