It’s easy to give away your personal information on the web without even realizing it. Big companies buy and sell your data all the time without you even knowing it, whether it’s based on the links you click or the products you research.

Facebook is known for having a particularly expansive knowledge of its users’ preferences, demographics, and habits, which it uses to target very specific groups for advertising. If you’ve ever wondered why you see the particular ads you see on your Timeline, it’s relatively easy to find out who is targeting you, and if they have your contact info. Find out how here!