Name changes due to the Islamic State
The Islamic State of Iraq and the Levant, often abbreviated as "ISIL", is a militant Islamist terrorist group. It is also known as the Islamic State of Iraq and Syria or the Islamic State of Iraq and ash-Sham, abbreviated as "ISIS" or sometimes simplified as Islamic State (IS) only — which has caused name changes to distinguish other entities from the group.
Source: Wikipedia — Name changes due to the Islamic State (CC BY-SA 4.0)