The invention of social media platforms in which every user move is automatically tracked was a major further step. The data benefit unleashed to social media providers such as Facebook was huge: through its Open Graph program, Facebook gained access to what users did not only on Facebook but also on every platform that users accessed via their Facebook ID—for example, Spotify. The result is what the industry, without irony, calls “people-based marketing.”

Nick Couldry & Ulises A. Mejias, The Costs of Connection, loc. 114