The article tries to analyze and evaluate the phenomenon of Islamic terrorism as an Islamic State. The author discusses the problems associated with the duality of this problem – stability and dynamism of this phenomenon. In this article the origin, identification and characterization of atypical terrorist organization, which is the Islamic State. Substantive content of this article includes both own thoughts, ratings and reviews, as and aspects presented based on documented sources of knowledge, and also based on media reports and other sources of knowledge and scientific documentary, which helped to create the image and the analysis of the socalled Islamic State. Islamic State from its inception was variously called – ISIS, ISIL, IS, DAESH. The most commonly used abbreviation is ISIS. It is an acronym for the Islamic State in Iraq and al-Sham (the Islamic State of Iraq and al-Sham). “Al Sham” refers to the region including Syria, Lebanon and part of Turkey and Jordan. ISIS was previously known as the ISI ( the Islamic State in Iraq) and adding a member of “al Sham” clearly gave the signal for further expansion and conquest of the whole region. Abbreviation ISIL is virtually the same as ISIS. The difference is only in the letter L, which refers to the Levant and not to al Sham, although basically is about the same region. In June 2014. ISIS announced that it changed its official name to the Islamic State (IS). DAESH is widely used in the Middle East and is an acronym hated by IS militants. DAESH word also has another meaning: ‘trampled’ or “shattered into dust”. Islamic State is probably the most specific creation which was built on the current international stage. To explain the phenomenon of this terrorist organization or a “quasi-state” should carry out an analysis of the facts which really is the so-called Islamic State. There are also other forms of naming as IS (ang. Islamic State) or ISIS (ang. Islamic State of Iraq and Syria) or from Arabic DAESH, which in themselves do not explain the essence of the organization and on the contrary only perpetuate the propaganda. ISIS is not the structure of the state as the name might suggest, although unambiguous definition of what is really ISIS is a high calling because of the manifestation of many key features.