It's Monday morning. You sign into your Facebook profile to update your status and you start due diligence on your friends' profiles. You're looking at photos from the weekend when you see that your girlfriend was tagged in an album of someone who is not your 'friend.' You click through to that person's profile to get the scoop on how they know each other. Then you see some mutual friends, click around a few more times and before you know it, you're looking at wedding photos of people you don't even know.
If you have a social networking profile, the above scenario probably seems all too familiar. (Trust me; there's a reason I was able to go through the steps of it so well...)