A lot of Facebook applications make it “better” if you have a lot of friends playing the game, bonuses, better chances of rewards, ability to buy things if you have so many friends etc.
This however can be a security risk to those that are so eager to play these games that they will add pretty much anyone they see playing the game so that they can get these edges.
Admittedly I enjoy games, I have been playing games since my fourth birthday when my parents bought me the Nintendo Entertainment System. I also very much enjoy some of these Facebook games which encourage adding others that play it. To protect myself I made some changes to my account that reduces the risk of Identity Theft and similar security issues.
If the steps are confusing or if you get lost, the gallery at the bottoms shows the section titles to help you along.