Popular Science: “Social media networks know a lot about you. In fact, that’s their primary job. They want to collect information about you and use that to sell advertisements that you can’t resist. In return for your data, these companies give you a chance to interact with other users and share your life no matter how interesting or banal. Recently, instructions have been floating around the web about how to see the secret interests Instagram thinks you want to see ads about. The results are sometimes hilariously wrong, but they can also be worryingly accurate. Your information is a product that companies leverage. In a perfect world, this exchange would result in a harmonious civilization in which people find others with similar interests and we enjoy our hobbies in peace. In real life, however, our information crawls around the dark corners of the web where it’s compromised, sold, leveraged, and otherwise abused. And that’s not even mentioning what happens when one of these social media sites flickers out of existence and takes all of your stuff with it. This article provides a quick primer on how to see what data sites have collected about you, as well as how to download and delete it. It’s handy information to have before the next site shuts down or accidentally tells a bunch of bad guys your favorite movie and your cellphone number…”