Virtualization is the process in which a server is partitioned into smaller components virtually.
Explanation:
Virtualization involves <u>running several operating systems at the same time</u> within a computer system.
In simpler words it is to create a virtual form of some real thing, such as a storage device.
For example, a <em>Hardware virtualization</em> would be to create a "virtual computer" that includes an operating system just like any normal computer, but the difference is that it runs virtually.