© Jim Edwards / Daniel Goodman / BI
It's free to use, of course, but that doesn't mean it comes without a price. If you're using Facebook, you're giving the company a ton of information about yourself which it is selling to advertisers in one form or another.
And most people forget that when they download or sign up for an app or website using their Facebook login, that they're giving those companies a direct look into their Facebook profiles and some of their personal data. That can often include your email address and phone number, but frequently also your current location.
If you're worried about your privacy, you can do two things: Opt out of ad tracking and - and this is sometimes rather alarming if you haven't done it in a while - look up the list of app companies that are logged in to your Facebook account.
We'll deal with the ads first, as that is easiest.
You can comfort yourself a little bit with the knowledge that the ads being targeted at you are coming anonymously and in bulk, at everyone who is in some way similar to you. They aren't literally being targeted at you personally, even if it feels that way. If you really don't like them, you can opt-out of most of them by following the instructions here and here.
If you want to go even further, by limiting the ad cookies that advertisers use to track Facebook users across the rest of the web, follow these instructions here and read this backgrounder here.
Now for the apps. That requires a bit more digging.
Here is the summary of where you need to go in Facebook's settings to see which apps are plugged in to your account: Settings > Apps > Apps you use > Show All Apps > Edit/delete. A more detailed set of instructions follows:
First go to the settings button on your Facebook page.
Scroll down and click "Settings."
