Business Insider

Jim Edwards

Aug. 12, 2015

Facebook is a great utility if you want to stay in touch with friends and family, share photos, and see what other people are up to in their lives.

It's free, 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 that it is selling to advertisers in one form or another.

Most people forget that when they download an app or sign in to a website using their Facebook login, they are giving those companies a look into their Facebook profile. Your profile contains a lot of personal information that can often include your email address and phone number as well as your work history and current location. And most people don't realize that if you're sharing any of that data with your friends, then apps used by those friends can see that data as well!

SNIP