Facebook's "ad preferences" page allows people to see themselves as Facebook does: a series of interests that can be used to make sure people see the ads that are most relevant to them.
It's accessed from Facebook's setting pages, or can be found by clicking here. Once you're on that page, you can click around to find out a lot about yourself – but the most important place to head to is "Your information" and then "Your categories".
The page will be more or less populated depending on how much time you spend on Facebook and what you do on it. The more you give to Facebook, the more it learns – and the more will appear on the page.
(The page also includes some other options, like the ability to hide certain topics. That means that people can choose to hide alcohol or parenting based ads if those issues are upsetting, for instance, either temporarily or forever.)
Facebook, of course, has far more data on each person than it shows on that page – it tracks everything a person clicks on, including after they've actually left Facebook. But that data is useful in large part for how the site turns it into information, which can then be sold onto advertisers who want to show certain things to certain people.
The page is a taste of how that all raw data is turned into the useful information for advertisers. So if Facebook sees that you keep coming to it using a certain smartphone, for instance, then competing manufacturers could buy ads to try and tempt you away; likewise if you seem to click a lot on articles about buying a house, then it might decide that you're in the market, and show you ads for new properties.
There are ways to keep Facebook from finding out all that data, if you wish.
The most obvious, of course, is to delete your Facebook account and never go on the site again. Indeed, it's this that the government and the EU will be giving people the power to do, allowing them to more easily scrub all of their information from the internet. But it can be done now by heading to the settings.
And you can also download an extension like Ghostery, which keeps some trackers from following you around the internet. That will mostly get rid of things far more malevolent than Facebook and its ilk, but you can set it to stop the blue behemoth from tracking you as well.
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