What is the 'PlayerStartTag'&'PlayerArray' in the MultiPlayer Games?

I have must uncheck the ‘Context Sensitive’, then can select it.

Anybody know?

PlayerArray in Gamestate holds all the PlayerStates that get created, one for each Player.

I dont know what playerStartTag is but I thibk it is a way to filter the PlayerStarts so that players pawns only spawn at thise with the matching tag. Something like that maybe.