When a friend of mine goes on Facebook, she gets all these things that come up that say 'Do you know' and then a name of someone. I can't work out how this happens and wondered if you good people might know.Many thanks.
You cannot, as far as I know, turn off Friend Suggestions (if that is what they are) in Facebook.
You CAN, in settings, limit Friend Requests (which is a different thing) to "Friends of Friends" (and not everyone). Friend Requests are from actual people, not from Facebook, and will trigger red notifications on your page.