Started in 2008, Facebook was initially the social site for students in Harvard University. Until now, it has been transferred to be the leading social networking site. Due to the success and popularity of Facebook, the site has been target of many scammers. Here is a list of Facebook's most common hacks and attacks and what will happen if you fall for them.
Phony Email Or Message
Facebook warns users that “The Facebook Team” or “Facebook” are likely to be scammers. These teams often require users to update accounts or ask for users’ names and password. Hence, it is advisable to ignore or delete the messages without clicking anything.

Phony Email Or Message
Clickjacking
Clickjackers on Facebook stimulate users to post the breaking and eye-catching information and headlines on their own wall. Once the Facebook users do so, clickjackers can control the accounts; send spam letters or messages to their friends.

Clickjacking
Fake Polls Or Questionnaires
If you click on an advertisement or a questionnaire and it links to another site outside Facebook, it is better to close the tab. The quiz sometimes requires your mobile phone or account address that is possibly harmful to your account.

Fake Polls Or Questionnaires
Rogue Apps

Many Facebook users complained that they have been victims of a fast-spreading scam which allows others to view the profile and talk you on Facebook.
Money Transfer Scam

If your friend send you a desperate-sounding message and ask for money transfer, you would probably be target of scammers.
Fake Friend Request

Despite Facebook's safeguards against bots, not all friend requests are from real people but from spamming accounts.
The Koobface Worm

The Koobface Worm
The Koobface worm, which appeared in December 2008, spread over the social networking sites like Facebook, MySpace and etc. The Koobface worm seriously affects your computer, hijack the Facebook profile and spam all friends.
Fake Page Spam

Events, invitations or malicious page are mostly from scammers rather than from friends.
Clickjacking Attacks: Most Common Hacks and Attacks on Facebook
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Facebook: Most Common Hacks and Attacks