It is not uncommon that people today, have several hundreds of "friends" on social media tools like Facebook. And it almost feels like, that the number of friends has become a symbol of status.
Therefore I think that this interview with the evolutionary anthropologist Robin Dunbar is very interesting. He claims that you cannot keep in contact with more than an average of 150 friends due to the limits of social skills in our brain. This also includes social media tools like Facebook.
These 150 friends involves relationships with trust and obligations not just names and faces. So how many of your "friends" on Facebook are real, actual friends?
You can find the interview here: