gas guns are allowed to be used on fields depending on what the fps restriction is but you wouldnt have to worry about that because most gbb dont go pass 340 fps, there are some that do and upgrades can get you there but typically most gbb do not go that far.
gbb stands for gas blow back , when you pull the trigger the slide blows back like a real pistol replica. no shell will eject but you get the idea.
its also a preference, some people like aegs but I am a gbb fan, so i only go to pistol night wednesdays in a cqb area "airsoftplayground" in california.
just my opinion but i think pistols are much more tactical and fun to use in cqb. we've had people with aeg's with box mags and hi caps unloading in such a small area, there really is no fun in that. pistols you can have more of a tactical game where you cant really waste too many bb's because your typically limited to 2-3 magazines depending on how many you bought.
yeah thats my insight.
but yeah man go search thats a pretty newbie question haha
