The realit is no such network that can brag that everyone is there. The biggest one, Facebook, doesn't even have a third of the total population on earth as act

The realit is no such network that can brag that everyone is there. The biggest one, Facebook, doesn't even have a third of the total population on earth as active users. Twitter, that we all love to talk about, has only a very small penetration with around 200 millions of active users. And there are still myriads of tiny web forums with very active communities. I don't think every social network needs to have a global penetration.