There are more than 1.5 billion Muslims and about 20% of them live in the Middle East and North Africa.
Muslims identify themselves with different strands of Islamic tradition. The main ones are Sunnism and Shiism. Accurate figures for the breakdown of the Muslim population into the various strands are not available as almost no censuses or surveys ask Muslims about which they are.
So the maps below show the estimated distribution of the Sunni and Shia populations within a percentage range of the total population.
The majority of Muslims are Sunnis - estimates suggest the figure is somewhere between 85% and 90%.
The Middle Eastern countries with the greatest proportion of Sunnis are Egypt, Jordan and Saudi Arabia, with Sunnis making up 90% or more of the population.
Shia make up roughly 10% of all Muslims, and globally their population is estimated between 154 to 200 million, according to a 2009 report from the Pew Forum.
Iran has the largest Shia majority, with more than 66 million making up nearly 90% of the population.
Shia are also in the majority in Iraq and Bahrain. There are sizable Shia communities in Kuwait, Yemen, Lebanon, Qatar, Syria, Saudi Arabia and the UAE.
In countries with large Shia communities, Shia often make up the poorest sections of society and see themselves as oppressed and discriminated against.