Well that’s self explanatory but will explain a few things here. Each folder is the style of the room i.e. Salon, pets room, corridor etc.

In those folders the room you have made say you use the salon and made your club with it you have backed up that room it will be stored in the "AdvPublic" leave alone less you do not want that room then just delete it but remember it will be gone for good. 

LEAVE WELL ALONE

If you are not too sure of the fact if you want it or not.