facebook allows 5000 friends which is really difficult to get on your own seeing as facebook limits the number of friend requests you can send and also "restricts" friending people you don't already know. this never made sense to me, what's the purpose of "social networking" if you're restricted in the way of networking?
what is "subscribe" and how does it work?
what is a "public" post and who can see it?
reasons why people "unfriend" others