Muslims believe that God revealed the Qur'an to Muhammad and that Muhammad is God's final prophet. The Qur'an and the traditions of Muhammad in the Sunnah are regarded as the fundamental sources of Islam.^[3][4] Muslims do not regard Muhammad as the founder of a new religion but as the restorer of the original monotheistic faith of Adam, Ibrahim and other prophets whose messages had become corrupted over time (or according to some authorities only misinterpreted).^[5][6][7] Like Judaism, Christianity, and the Bahá'í Faith, Islam is an Abrahamic religion.^[8]

Today, Muslims may be found throughout the world, particularly in the Middle East and North, West and East Africa. Some of the most populous majority-Muslim countries are in South and Southeast Asia. Other concentrations are found in Central Asia. Only about 20 percent of Muslims originate from Arab countries.^[9] Islam is the second largest religion after Christianity in many European countries, such as France, which has the largest Muslim population in Western Europe, and the United Kingdom.^[10][11]