Islam
In 2009, a study was done in 232 countries and territories. This study found that 23% of the global population or 1.57 billion people are Muslims. Of those, between 75% and 90% are Sunni and between ten and twenty five percent are Shi'a.  A small part belong to other Islamic sects. In about fifty countries, more than half of the people are Muslim.  Arabs account for around twenty  percent of all Muslims worldwide. Islam has three holy sites; Jerusalem, Mecca and Medina.