Virtualizing servers refers to running multiple server environments on a single physical piece of hardware.  By introducing a thin layer software, which contains a virtual machine monitor or a hypervisor, the hardware can allocate its resources between many different virtual servers simultaneously. Also, the problems or fails that occur on one server do not affect the other servers. The number of virtual machines that can run on a physical machine depends on the power of the physical box.

By maximizing the resources of one server you increase energy efficiency, reducing your overall energy costs, you will have increased agility and flexibility to create different operating systems on the fly, to restore systems in post-disaster environments, and to create redundancy internally and you will have lower total cost of ownership on your hardware as well since you will have fewer physical servers to maintain.

Why virtualize your servers? Because it just makes cents!