Iraq crisis: The Sunni-Shia divide explained
21 June 2014 Last updated at 13:59 BST
One of the factors behind the most recent violence in Iraq is the sectarian divide between Sunni and Shia Muslims in that country.
The majority of Iraq's Muslims are Shia, and the Isis militants gaining ground there are Sunni.
According to the Pew Research Center, Iraq is one of only a handful of countries with a Shia majority.
So how do opinions of Islam in Iraq compare to other countries in the region?
The BBC's Ashley Semler looks at the numbers.
Produced for the BBC by Bronson Hoover