https://medium.com/@cnn/its-not-just-facebook-thousands-of-companies-are-spying-on-you-f5890f325db1

By Bruce Schneier

In the wake of the Cambridge Analytica scandal, news articles and commentators have focused on what Facebook knows about us. A lot, it turns out. It collects data from our posts, our likes, our photos, things we type and delete without posting, and things we do while not on Facebook and even when we’re offline. It buys data about us…