Islam, a universal religion

: Currently Islam is the second largest religion in the world after Christianity. A comprehensive demographic study of more than 200 countries finds that there are 1.57 billion Muslims of all ages living in the world today, representing 23% of an estimated 2009 world population of 6.8 billion (Pew Forum on Religion & Public Life 2009).

Not all Muslims are Arabs: 

Arab Muslims constitute less than one fourth of the total number of Muslims in the world.

There are approximately 2.1 billion Christians in the world representing 32% of world’s population and 1.1 billion non religious / atheist people in the world (15% of world’s population). Judaism represents 0.22% of world's population (approx. 14 million people).