"The Islamic State (IS, aka the Islamic State of Iraq and the Levant, ISIL/ISIS, or the Arabic acronym Daesh) is a transnational Sunni Islamist insurgent and terrorist group that controls large areas of Iraq and Syria, has adherents in several other countries, and disrupts regional and international security with violence and terrorism. A series of terrorist attacks attributed to the group outside of Iraq and Syria during 2015 has demonstrated IS supporters' ability to threaten societies in the Middle East, Africa, and Europe, including in countries with sophisticated and capable intelligence and security forces. […] This report provides background on the Islamic State organization, discussing its goals, operations, and affiliates, as well as analyzing related U.S. legislative and policy debates."
CRS Report for Congress, R43612
Federation of American Scientists: http://www.fas.org/sgp/crs/index.html