The social networking website Facebook has more than 500 million active users which is about one person for every fourteen in the world. Users add friends and send them message and update their personal profiles. With these features, Facebook games are popular in the game world because users can play with all the friends together.

However, do you really know all about Facebook? Below are 10 Facebook-related things that common people may not know. What about you?

1. "Over-sharer" refers to the one who publicly shares most details about his/her life.

2. Marc Zuckerberg, founder of Facebook who's only 26 years old, just lived in an apartment with no TV sets, though being the world's youngest billionaire.

3. Facebook's logo is blue-white, because Zuckerberg is a red-green colorblind man and blue is the most beautiful color he can see.

4. There's also an app market on Facebook, and users can enjoy free trade there. The market is just called "Marketplace".

5. MTV showed interest in buying Facebook with USD 57 million in 2005, and Yahoo and Microsoft's offers were even higher. But Zuckerberg refused them all.

6. In 2004, Zuckerberg established Facebook in his dormitory room.

7. Zuckerberg has over 661,000 fans and friends on Facebook, including his parents and 3 sisters.

8. Obama is the first president who ran for president on Facebook.

9. Goodluck Jonathan, President of Nigeria, first announced to participate in the next presidential campaign on Facebook.

10. Facebook started to offer localization services in UK last Friday, and will march into Germany soon.