Never get scammed on Facebook!
Avoid those fake "Login with facebook" sites. Some of them may be fake, and hack your Facebook account immediately. If your contact information get in the wrong hands, it can turn out very bad.
Install this extension, and always look for the little "fSafe" icon in the top right of your search bar.
fSafe has over 30 listed secure pages.
NOTE: Facebook apps on own risk, you never know which coding they contain!
I think Facebook should have made a program like this a requirement, for all companies associating with Facebook.
Excuses for my less good English, but so far I'm just a 15 year old Danish school student.