Hi JM,
it's not required; but, there are some cool virtualization resources out there now--say you are running XP, but, you are getting tired of it picking up malware while browsing, etc: create a virtual XP machine, browse with that--if it gets crapped up, no big deal, because all the crapware is gone when you close that virtual machine....you can then create another one, etc.
Or, run XP and Linux in virtual machines on the same machine.
For servers, since CPUs are so powerful now and have multiple cores, instead of having say 4 physical servers to do 4 things: say email, a SQL database, web serving, etc, just get one physical machine and create 4 virtual servers on it--that way instead of the powerful CPU running at 1% all the time, it gets more fully employed, you save space, energy, cooling costs, and, maintenance time as well.
Here is a good reference from VMware:
http://www.vmware.com/virtualization/
http://www.vmware.com/overview/why.html
HTH
NXIL
From Wikipedia:
http://en.wikipedia.org/wiki/Virtualization
Virtualization examples
The following examples illustrate applications of virtualization.
Server consolidation
Virtual machines are used to consolidate many physical servers into fewer servers, which in turn host virtual machines. Each physical server is reflected as a virtual machine "guest" residing on a virtual machine host system. This is also known as Physical-to-Virtual or 'P2V' transformation.
Disaster recovery
Virtual machines can be used as "hot standby" environments for physical production servers. This changes the classical "backup-and-restore" philosophy, by providing backup images that can "boot" into live virtual machines, capable of taking over workload for a production server experiencing an outage.
Testing and training
Hardware virtualization can give root access to a virtual machine. This can be very useful such as in kernel development and operating system courses.[2]
Portable applications
Certain application configuration mechanisms such as the registry on the Microsoft Windows platform lead to well-known issues involving the creation of portable applications. For example, many applications cannot be run from a removable drive without installing them on the system's main disk drive. This is a particular issue with USB drives. Virtualization can be used to encapsulate the application with a redirection layer that stores temporary files, Windows Registry entries, and other state information in the application's installation directory ? and not within the system's permanent file system. See portable applications for further details. It is unclear whether such implementations are currently available.
Hardware virtualization technologies
* Intel Vanderpool x86 virtualization
* AMD Pacifica x86 virtualization
* Sun UltraSPARC T1 hypervisor
* IBM Advanced POWER virtualization