Islam is the world's second largest faith with more than a billion followers, who are called Muslims.
Islam means submission to God, who is known as Allah, and committed Muslims expect to spend their lives serving God.
Muslims believe Islam was revealed to humanity in the 7th Century, when the Angel Gabriel appeared to the Prophet Muhammad to reveal verses sent by Allah.
The words are believed to have been written down during Muhammad's life, forming the Muslim holy book the Koran.
Muslims believe Allah is the one and only God. Obedience to the will of Allah, who created and rules everything is at the heart of all Muslims' faith.
Muslims believe in the Old and New Testament prophets sent by God. Muhammad is considered the final prophet.
Becoming a Muslim involves saying the Shahada: "I bear witness that there is no God but God, I bear witness that Muhammad is the prophet of God."
Muslims believe the Koran is the word of God and in the Day of Judgement.
Muslims are expected to live according to the Five Pillars of Islam.
The first is reciting the Muslim profession of faith sincerely. The second, Salat, involves performing ritual prayers five times daily.
Zakat means paying an alms for the poor, while Sawm involves fasting for the month of Ramadan. Those who are able to must make the Hajj to Mecca.
A committed Muslim believes fulfilling these obligations shows they are putting their faith before anything else.
Muslim places of worship are known as mosques. The Arabic word is masjid.
Although a special building is not required for worship, many mosques have minarets from which the call to prayer is made.
Before entering a mosque, worshippers remove their shoes and conduct a ritual washing. Everyone sits on the floor and is considered equal.
Women can attend mosques, but must sit apart from men. It is commonplace for women to pray at home instead.
There are two main Muslim sects, the Sunnis being the largest - making up 90% of the world Muslim population.
The other main group is the Shias, who make up a significant minority in many countries and are a majority in Iran.
The shared faith is considered a strong bond, but there is often conflict. There are also variations in the way diferent groups practice their faith.
Muslims respect Christians and Jews as they consider them members of the family of Abraham, one of the prophets.