But what most people don’t realize is that they have ways of tracking your offline purchases as well. Now obviously, Facebook knows what its users buy when they click on ads from Facebook. And location data could reveal other people who live in your house, even if you’re not connected to them on Facebook. And they use this information to target ads at you. If you have location tracking turned on, Facebook collects an enormous amount of location data about where you’re going, where you came from, where you live, where you work, what restaurants and businesses you tend to go to. Researchers have found that by using signals such as your likes and interactions, Facebook could tell if you were in a relationship or going through a breakup. This would include basic stuff like your age and gender, but also more complicated information like whether you own a motorcycle or you recently went on vacation or whether you’re a gadget geek. Facebook uses nearly 100 different data points to classify your interests and activities. Facebook can take all the data that you submit and combine it with data from other users and outside information to construct a profile of you. But Facebook has much more data on most people than they realize. We submit things like our names, our hometowns, our ages, our birthdays and our interests, and we assume that Facebook is collecting that data. Most people know that Facebook has information about them. Kevin Roose, a technology columnist for The Times, explains.

The information you share in your profile is a mere snippet of what Facebook and its partners really know about you.

Transcript Does Facebook Know You Better Than You Do? What makes you tick, whom you know, where you go, even where you might end up.

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