It looks like [almost everybody from the old days](http://harry.sufehmi.com/archives/2006-06-28-1192/) always uses ‘invert/reverse’ mouse setting when playing [FPS games](http://en.wikipedia.org/wiki/First-person_shooter). On the other hand, new gamers almost certainly use the so called ‘normal’ setting. In ‘invert/reverse’ mode, in order to look upwards we pull our mouse back, and to look downwards we push our mouse forward. The reverse is true in ‘normal’ mode. Somehow, these new players will scoff at ‘invert/reverse’ mode and find it very disorienting, and yet be amazed when ‘invert/reverse’ players regularly beat them :).
Why older gamers love their ‘invert/reverse’ mouse setting so much?
Probably because [flight sims](http://en.wikipedia.org/wiki/Flight_simulator) predate FPS games by a few years, and these people (including me) used to play flight sims before they played their first FPS game. In flight sims, the controls try to mimic the controls used in real aircraft. We pull back the stick to climb and push it forward in order to descend. Most flight sims were designed to use joystick, but some can also accept keyboard and mouse input. A very popular flight sim game, [Star Wars: X-Wing](http://en.wikipedia.org/wiki/Star_Wars:_X-Wing) and its subsequent games in the series were popularly played using a mouse because it required high precision control that were only present in expensive joysticks.
When an aircraft is going to hit the ground, people on board will scream “PULL BACK! PULL BACK!” Had the control uses the so called ‘normal’ setting, ‘pulling back’ will only make the plane hit the ground much sooner :).
The first FPS game that supports vertical controls, [Duke Nukem 3D](http://en.wikipedia.org/wiki/Duke_Nukem_3D), also uses the setting known today as ‘invert/reverse’ as default. In fact, its ‘invert’ feature actually made the control behave like today ‘normal’ mode.
It might be more natural to use ‘invert/reverse’ setting to think of the movements of our heads. In order to see a higher object, we lean our head back. And to see a lower one, we push our heads forward. In this view, it is more natural to use ‘invert/reverse’ setting. And more so if a trackball is used instead of a mouse.
And why these new gamers use ‘normal’ setting? Primarily because almost all FPS games today use the so called ‘normal’ setting by default. And maybe for some people it is actually more natural to use ‘normal’ setting, even in flight sims! I can remember a friends who wondered why his plane won’t take off: because he pushed forward, not pulled back. But eventually all flight sims players get accustomed to the control, simply because there were no option to reverse the setting.
My little brothers (12 and 16 years younger) used to play with ‘invert/reverse’ mouse because they had their turns to play after mine :). And they were too young to know what the ‘proper’ settings should be :). But since they started to play with their friends, they had to get used to ‘normal’ mouse because their friends made the case that their mouse setting somehow always get screwed after my brothers’ turn :).
In [Counter-strike](http://en.wikipedia.org/wiki/Counter-Strike) sessions among office mates, the team I’m a member of regularly beat the opposing team. After an overly long series of shameful defeats, they started to closely observe how I played. One thing that got noticed was that I played with ‘invert/reverse’ mouse. Afterwards they tried playing with ‘invert/reverse’ mouse, but of course it would only make it easier for me to win the game :). They gave up using ‘invert/reverse’ after a while :).
According to several informal surveys ((http://myunreal.com/showthread.php?t=74965), (http://nokytech.net/forum/showthread.php?t=56960)), only 10-20% of all players use ‘invert/reverse’ mouse.