With increasing daily usage of PC, computer networking, work stations and servers, software environments are changing continuously. Therefore it is necessary to use a operating system and incorporate environment, increasing efficiency, source division and clear management for solve relative problems. Of course, in these operating systems, distributing sources, software an d other things should be hidden from user view. Cloud operating system consider a set of PC, sources and software (hereafter, which we named them nodes) in whole and produce a centralized system. In fact, this operating system is a controlling pr ogram which performs on a network including a set of computers. This program change network in a calculating and informational source. This paper is about structure, the way of performance and also properties of some kind of operating systems and finally it do some research about existing challenge about this kind of operating system.