Virtualization basically refers to the abstraction of the computer resources and interfaces running under the external interfaces. It hides the technical details going on under the software running or being used by an end user.
Virtualization could mean the simulation of computer environments. It could also mean the simulation of fragmented or combined resources. The trend now though is more for the recreation or simulation of computer environments so that other or guest software can be introduced and run under it. What this type of IT virtualization requires is a host software that will enable the virtualization to happen. Under a given hardware platform, a guest software is introduced and run so it can be used by more or a different set of end users. The guest software is now able to perform or run as if it was running under a new separate hardware resource. When hardware is simulated, the service rendered is extended. The hardware’s use is doubled and its use can even be diverted into some other ways.
Most people would do IT virtualization to optimize and maximize on its resources and in order to serve more people. Virtualization is now a trend in order to save on acquisition cost of hardware as well. From the point of view of businesses, they do this to cut cost and to be cost efficient. The more uses and the more productive they get from a given resource the more efficient they become and the better bottom line they will have.