If you are interesting in running multiple Operating System within your current Operating System at a same time, then these software would be of great help to you. The software through which we can accomplish such tasks are known as Virtual Machine. A Virtual Machine is a software implementation of a computer that performs like a physical machine. System machine and Process machine are it`s two types where first one is used to provide a complete system platform on which we can run different Operating System and the latter one can be used to run a single program. Now there are lots of such software`s out there on the web. So here I`ve chosen some of the popular one`s(System Machine).