What are the "poeple you may know" on Facebook?

On the side of your profile it has people you may know and usually lists 2 names at a time? Usually the bottom name is somebody I have quite a few mutual friends with. But the top name is some random person with 0 mutual friends and are usually from another country half way across the world. Why does it advise these people? Is it just a glitch (this always happens to me) or is it some kind of subliminal system to get different cultures connected?