and a happy sunday to you. 'Groups' seems to be an 'add on' feature to vBulletin (the board software that is used by talking point).
It allows administrators to set up a hierarchical forum with different levels of groups all with interlinked permissions. May be useful in the MOD or CIA but not much use the talking point which is why the feature is probably unused. That's my take on it anyway. You can find out more at the vbulletin forum......