This morning’s Observer column.

At a Royal Society symposium on web science this week, Tim Berners-Lee let slip an interesting observation. Many people, said the web's inventor, no longer make a distinction between Facebook and the web. My guess is that these people are mainly teenagers – those whose experience of cyberspace is coloured by the fact that the first thing they encountered online was social networking. They started with Bebo and MySpace and then graduated to Facebook. And there they have stayed.

So, for them, Facebook is where it's at. That explains why they no longer use email, for example, except – grudgingly – to collect official communications from school or college. Most of their electronic communications are routed either via text messaging or Facebook updates. Almost all teenage party invitations now come via Facebook, which has also become the logbook of their lives. When it was announced a couple of weeks ago that Flickr, the photo-hosting site, had hosted its five billionth picture, someone pointed out smugly that Facebook already has over three times that number…