Talking in 2010, Mark Zuckerberg, the founder of Facebook, announced that privacy is no longer a “social norm”. In the future, data on our habits and movements – where we’ve been and what we’ve done – will be available to anyone who wants to know. Thanks to image-recognition software, we’ll be able to identify anyone who we point a phone at; when we shop online, prices will be tailored according to our income and willingness to pay; and when we go to the airport, aviation authorities will know so much about the minutiae of our lives it will no longer be necessary for us to queue for security. In fact, there is so much personal data on the web that Eric Schmidt, the co-founder of Google, has warned that teenagers might be forced to change their names one day in order to escape their cyber past.