Server virtualisation runs on the technology called “hypervisor” . It runs on top of the system hardware . It becomes a thin interface between Operating System (OS) and the hardware it depends upon. Hypervisor supports multiple OSs running paralled or isolate to each other. Hypervisor make each OS behave as separate machine , thus each OS is known as virtual machine. So, clearly on a single piece of hardware multiple virtual machines are running. The resource allocation of base machine can be changed dynamically by hypervisor , according to demands by virtual machines. This shows optimum utilisation of base machine to its fullest. How exactly does virtualisation help? Here’s how…Back up of virtual machine is easy and in some case it has the mobility, as it can be install on different base system subject to meeting of standards and resources. So, in a way it is a tool for disaster recovery. As through virtual machines, it minimises cost in a multifaceted way as it stops making multiple base machines thus cutting the power and cooling expenses. Virtual machines can be used for testing of softwares so as to say a saving grace for software developers without hurting the base system at all. With multiple virtual systems on a base system, average utilisation of dat6a flow will be lower as it can divide the process of data flow into various segments , thus minimising the base failure, making a saving grace for you and for yours organisation.