using only a monitor, keyboard, and mouse?

what are these devices going to be connected to?

virtualisation allows you to have multiple "virtual" operating systems on the single physical computer.

Hi,
I want one physical computer server which people using multiple monitors ,keyboards and mouse can operate at the same time but they don't share the same screen they have their own instances.

I am not sure if virtualization can help me here.

Cheers,
Vishal

not really, you just need a "server" edition of a OS. BUT you still need computers for each user, unless they are sitting in front of the same computer.

You might want to look into a thin client server. The user's machines connect to the server on boot and the server "gives" them an OS that is running as an instance on the server... So all the processing is being run on the server, and the end user's machine is only used for display.

~Mike