We already knew that Facebook is tracking our every move on the web, just like everyone else is, but now the social network says it's going to use data from the other sites we visit and the apps we use to deliver more relevant ads. If you want to opt out of this enhanced behavioural targeting, there's a form for that.
Facebook's ads up until now have been mostly from things you do on Facebook and the stuff you (or your friends) like. In an announcement today, Facebook says it's going to start including information from elsewhere, explaining it like this:
Let's say that you're thinking about buying a new TV, and you start researching TVs on the web and in mobile apps. We may show you ads for deals on a TV to help you get the best price or other brands to consider. And because we think you're interested in electronics, we may show you ads for other electronics in the future, like speakers or a game console to go with your new TV.
On first glance, this might sound great -- "interest-based ads" that are more relevant to you, versus generic belly fat ads. However, this kind of tracking can be insidious as well: your activities online and other personal information (such as location, age, medical habits) are collected and added to databases to create a profile of you for marketers.
You can opt-out of Facebook and more than 100 other companies from collecting this data for online ad purposes at the Digital Advertising Alliance. Participating companies agree to respect consumers' opt-out preferences for these kinds of interest-based ads. When you opt-out, a cookie is placed on your browser, and it has a minimum five-year lifespan.
Note, however, that opting-out won't stop companies from serving any ads or collecting any data at all. Sites can continue to collect and use information for purposes other than online behavioural advertising, such as detecting if you're a return visitor or the number of times an ad has been shown to you. If you want fuller control over sites' activity tracking, you'll probably want to install a browser extension that does that.
As with opting-out from companies that mine our data, at least we have an option to tell companies to stop. (Note: Facebook is also rolling out an ad preferences feature, where you can click on an ad and tell it not to show you any similar ads in the future.)