When scrolling through your morning newsfeed, you encounter an ad so eerily well suited that you wonder if someone has possibly read your mind. Maybe a birthday is coming up, and Facebook is showing ads for a local florist. Or maybe you just made a joke aloud about how much you crave ice cream and Instagram is promoting Ben and Jerry’s. Whatever the subject is, you’ve probably seen ads like this and wondered, or even worried, how they found their way to you.

Many people believe that approving sites and apps to collect our personal data won’t do any harm as long as we don’t have anything to hide. Neither do we consider how the use of gathered information can affect other areas of our lives without our knowledge. When finding out that Facebook had been making targeted advertising based on users personal data that could have affected the 2016 American election(1), it became very clear how big the effect can be when the gathering of personal data is used inappropriately. Another thing we don’t know is what the use of personal data will look like in the future. Already today companies offer discounts on their services if you allow them to track your behavior. Life insurance companies lower prices if you walk a certain amount of steps a day, and auto insurance companies can ask you to install a device that monitors how safe you drive to give you a policy discount (2). What if they decide they won’t let you get life insurance if you have diabetes? Or if you are considered as having risky behavior since you joined the group “YOLO” on Facebook. How much does this gathered data really say about us? And maybe you don’t care about your privacy today, but what if it gets into the wrong hands tomorrow?