The FN P90 was developed as an attempt to replace the 9mm cartridge with Nato forces. Its 5.7 cartridge is a high velocity low recoil round that does better on soft body armor than easily defeated 9mm. Its a closed bolt, magazine fed machine gun. The P90 is often chosen to represent futuristic weapons in sci-fi movies and tv shows. One interesting note: when the P90 is in full auto it has two trigger positions. The first pull gets you one shot in semi and if you pull even harder (further to the rear) then you get the full auto burst.