These are the multiplayer settings in the game Divinity: Original Sin:
This determines who will be able to join you when you play the game. There are four distinct settings that can be changed at any time within the game by hitting the diamond button that is over the in-game minimap.
No one can join your game. Select this option if you prefer to journey alone.
Only people who you have specifically invited can join your game. Select this option if you don’t want people joining your game without an invitation.
Anyone from your friends list can join your game. Select this if you are fine with your friends joining your game at any time.
Anyone can join your game. Select this if you don’t mind strangers joining your game at any time.