Islam is a major world religion with over 1.8 billion adherents. It is the second largest religion in the world after Christianity and is based on the teachings of the Prophet Muhammad. Islam is an Abrahamic faith, meaning it shares many beliefs with Judaism and Christianity, such as the belief in one God and the importance of prayer and charity. The core beliefs of Islam include the belief in Allah as the one true God, the belief in angels, the belief in prophets, and the belief in the Day of Judgment. Muslims also believe in the Quran as the word of God and follow the five pillars of Islam: faith, prayer, charity, fasting, and pilgrimage.