What is virtualization?

What will be an ideal response?

Virtualization is the process by which one physical computer hosts many different virtual (not literal) computers within it. One operating system, called the host operating system, runs one or more operating systems as applications. Those hosted operating systems are called virtual machines (vm). Each virtual machine has disk space and other resources allocated to it. The host operating system controls the activities of the virtual machines it hosts to prevent them from interfering with one another. With virtualization, each vm is able to operate exactly the same as it would if it were operating in a stand-alone, nonvirtual environment.
Three types of virtualization exist:
• PC virtualization
• Server virtualization
• Desktop virtualization