Why use a VM?
Server consolidation is a top reason to use VMs. Most operating system and application deployments only use a small amount of the physical resources available when deployed to bare metal. By virtualizing your servers, you can place many virtual servers onto each physical server to improve hardware utilization.
This keeps you from needing to purchase additional physical resources, as well as reducing the need for power, space, and cooling in the datacenter. VMs enable failover and redundancy that could previously only be achieved through additional hardware.
A VM provides an environment that is isolated from the rest of a system, so whatever is running inside a VM won’t interfere with anything else running on the host hardware.
Because VMs are isolated, they are a good option for testing new applications or setting up a production environment. You can also run a single purpose VM to support a specific process.