All of this saves a lot of money, as an hour in the simulator costs less than a third of what an hour flying the actual aircraft would cost. Also, you can do more dangerous things in the simulator, including training for catastrophic emergencies (loss of key parts of the aircraft due to battle damage or equipment failure.) It's safer for new pilots to try difficult maneuvers in the simulator first, before they do it in the actual aircraft.
The Canadian Air Force is buying six CF-18 aircraft simulators for $25 million each. The simulators will be networked and enable the pilots to operate all the cockpit equipment they find in the actual aircraft, as well as coordinate operations with other simulator pilots. The simulators provide some motion, and 360 degree 3-D graphics inside a dome. The simulators are so expensive, nearly as expensive as the aircraft they simulate, because they achieve a very high level of realism. This involves very realistic images of what the pilot sees and a complex hydraulic system to move the cockpit about in a realistic fashion. There are also accurate sound effects. PC based flight simulators have also proved useful, especially during the last few years as realistic 3-D PC graphics became available. But the additional elements of the "professional" simulators provides an experience close enough to the real thing to create an effective substitute for actual flying.