A: It means First Person Shooting Multiple Dungeons. It is smaller then a MMORPG. This game has rooms ranging from 8 to 16 members. If you ever played gun bound or American Army it is sort of like that in rooms. Further more it is really a 3rd person shooting but we consider it a First person because that is what the genre title is.
It's not an FPS. It's a third person because you don't see it from your character's point of view, rather the camera is positioned behind your character.