Virtualization has been around in one form or another since computers were first invented. They are also a standard features on Mainframes. Even on the ubiquitous Intel x86 platform, virtualization has been available for a long time now. However, with the introduction of technologies like VT(code-named Vanderpool) from Intel and AMD-V(code-named Pacifica), hardware assistance provides performance benefits that were lost when traditional techniques involving emulation were employed. Though VT/AMD-V technologies provide you the ability to run multiple, unmodified operating systems on servers, a lot of effort has gone into container based technology for Linux. Container based virtualization does not allow you to run unmodified operating systems from different vendors, but allows you to run multiple Linux distribution instances from varied vendors on a Container based Linux machine.

There are many advantages of virtualizing your data center including the following:

Save the cost of buying hardware. Increase your hardware utilization. The reduced physical hardware calls for fewer maintenance personnel. You don't waste time on software installation. You can clone existing servers in minutes. Simplify backup and restore operations. Give yourselves the advantage of high availability since your virtual servers aren't tightly bound to physical servers and you can move them other physical servers in case one of them goes down or has to be taken down for maintenance. Using virtual appliances, deploy commonly used services in a jiffy. They even manage themselves. Don't underestimate how much you can save of electricity