Rory Cellan-Jones looks at the social networking sites of the future and asks where the phenomenon is heading. New sites are springing up all the time. The future of social networking could lie in localised sites geared towards specific interests, in limiting your online circle to your closest...

Rory Cellan-Jones tells the story of the social networking scramble of the early 2000s and finds out how Facebook emerged to become world's biggest social network. Facebook wasn't the first site of its kind - other businesses had a lot in common with Mark Zuckerberg's efforts - but its...