Virtualization refers to the creation of a virtual resource such as a server, desktop, operating system, file, storage or network.
The main goal of virtualization is to manage workloads by radically transforming traditional computing to make it more scalable.
Virtualization has been a part of the IT landscape for decades now, and today it can be applied to a wide range of system layers, including operating system-level virtualization, hardware-level virtualization and server virtualization.
Virtualization technology involves separating the physical hardware and software by emulating hardware using software.
When a different OS is operating on top of the primary OS by means of virtualization, it is referred to as a virtual machine.
A virtual machine is nothing but a data file on a physical computer that can be moved and copied to another computer, just like a normal data file.
The computers in the virtual environment use two types of file structures: one defining the hardware and the other defining the hard drive.
The virtualization software, or the hypervisor, offers caching technology that can be used to cache changes to the virtual hardware or the virtual hard disk for writing at a later time.
This technology enables a user to discard the changes done to the operating system, allowing it to boot from a known state.