 Military simulation, military simulations, also known informally as war games, are simulations in which theories of warfare can be tested and refined without the need for actual hostilities. Many professional analysts object to the term war games as this is generally taken to be referring to the civilian hobby, thus the preference for the term simulation. Simulations exist in many different forms, with varying degrees of realism. In recent times, the scope of simulations has widened to include not only military but also political and social factors, which are seen as inextricably entwined in a realistic warfare model. Most many governments make use of simulation, both individually and collaboratively. Little is known about it outside professional circles. Yet modeling is often the means by which governments test and refine their military and political policies. Military simulations are seen as a useful way to develop tactical, strategical and doctrinal solutions, but critics argue that the conclusions drawn from such models are inherently flawed, due to the approximate nature of the model used.