you can read this paper it's useful and  can satisfy your question :

""RUM Extractor: A Facebook Extractor for Data Analysis"" 

Conference Paper RUM Extractor: A Facebook Extractor for Data Analysis

http://www.informationweek.com/big-data/big-data-analytics/facebook-on-big-data-analytics-an-insiders-view/d/d-id/1109106?

https://www.linkedin.com/pulse/20140716060957-64875646-facebook-and-big-data-no-big-brother

http://blogs.wsj.com/cio/2013/10/31/heres-how-facebook-manages-big-data/

Thanks for the help Mosab Mohammad Faqeeh, but I want to find something about how to facebook uses hadoop and big data. If someone can help more I appreciate it.

Hello,

FaceBook uses Hadoop in every product it offers from likes and status updates to messaging services in different ways, Both SQL and NoSQL database approaches are used for different purposes and products. The following links deliver more information:

http://hortonworks.com/big-data-insights/how-facebook-uses-hadoop-and-hive/

http://www.infoworld.com/article/2616022/big-data/facebook-pushes-the-limits-of-hadoop.html

You may like following article to refer:

http://www.informationweek.com/big-data/big-data-analytics/facebook-on-big-data-analytics-an-insiders-view/d/d-id/1109106?