What is Virtualization?

What is Virtualization, and how many types of Virtualization exist?

Virtualization is a technology that enables the simultaneous execution of multiple operating systems and programs on a single piece of hardware. This technology is implemented by software called a ‘hypervisor’ or ‘virtualization monitor,’ which allows the execution of multiple virtual machines (VMs). Each VM can independently run a different operating system and various programs on a single server or hardware unit.