Boko Haram, officially Jama'atu Ahlis Sunna Lidda'awati wal-Jihad, which in Arabic means "People Committed to the Propagation of the Prophet's Teachings and Jihad," is a Nigerian Sunni Muslim militant group. The group wants the overthrow of Nigeria and has killed thousands of people, including 44 people on Christmas day 2011,  coordinated attacks that killed at least 185 people on January 20. 
Muslim cleric Mohammed Yusuf formed Boko Haram in 2002. They publicly proclaim allegiance to al-Qaida.
The United Nations has designated Boko Haram a terrorist organization, and has established a counterterrorism center in Saudi Arabia to coordinate efforts to combat the group's activities in Nigeria, Sudan and South Sudan. 
- Who are Nigeria's Boko Haram Islamists?, BBC, January 11, 2012
- 'We will attack Nigeria again and again', Boko Haram leader vows, The Telegraphe, January 27, 2012