The friends who never leave
Facebook isn’t the only stranger learning all about you. People are increasingly mobile; they go to college thousands of miles away from home, take jobs in other states, and occasionally go live the life of an expatriate in some romantic foreign destination. Such a change used to mean losing contact with all but those friends willing to engage in an extended correspondence, even though the chances of seeing you alive again were remote. Moving to another city was like being eaten by bears—your friends would miss you for a short time, but most of them would quickly forget you except as an interesting anecdote.
Now, you can easily reconnect with people you haven’t seen in twenty years. Your Facebook friends list is potentially hundreds of people, most of whom you barely know at all (and some of whom you might actively dislike), but they all have access to your most intimate details.
Facebook has a goal above and beyond allowing you to reconnect with all the people you secretly hated in high school. Facebook knows you—sometimes better than you know yourself—and it’s determined to keep learning more about you.