the exploitation of data extracted from people's past behaviours [...] allows increasingly accurate predictions of their future behaviours.
The author demonstrates that the value of large digital companies (including Facebook and Google) comes from the exploitation of data she calls “behavioural surplus”: data that is not generated by the user via the main service of a platform. For example, the value created by a search engine is not so much the result of the words searched but rather of the exploitation of cookies (pieces of code containing information about the user, left on his or her browser by the websites he or she visits). It is the latter that allows a fine profiling of Internet users without their knowledge. Thus, the exploitation of data extracted from people's past behaviours (online, but also and increasingly in the physical world, with the development of mobility platforms, payment services, smart cities, etc.) allows increasingly accurate predictions of their future behaviours.