Yes, it is for structuring the wiki pages. I read about structures and already tested them. I'm not a friend of the menu that shows up at the top of the pages that are in the structure. Is it possible to hide that completely when using structures? Even now that I completely deleted the structure, those pages show the structure button on theyr top right, where you can activate and deactivate said top menu - it just is an empty leftover. Maybe it's a bug, maybe not. I'm too unexperienced to say.
About your second link: This is the whole paragraph it links to:
See "Structures User" -> Dead Link
You can either make a navigation menu from a "menu Id" or from a "structure Id". -> How do I do that? Is that the top menu that shows up automatically?
All in all, this text doesn't help.