Muslims believe that God revealed the Qur'an to Muhammad, God's final prophet, through the angel Gabriel, and regard the Qur'an and the Sunnah (words and deeds of Muhammad) as the fundamental sources of Islam. With 1.3 billion to 1.8 billion Muslims, Islam is the second-largest religion in the world and the fastest growing religion in the world. The word Muslim is the participle of the same verb of which Islām is the infinitive. An adherent of Islam is known as a Muslim, meaning "one who submits ".
Other meanings include submission, or the total surrender of oneself to God (Arabic: الله, Allāh) (see Islam (term)). The word Islam is a homograph having multiple meanings and a triliteral of the word salam, which directly translates as peace. Islam (Arabic: الإسلام al-’islām, pronounced ( listen)) is a monotheistic, Abrahamic religion based on the teachings contained in a religious book, the Qur'an, considered by its adherents to be the verbatim word of Allah (the sole divine entity in Islam) as revealed to the Islamic prophet Muhammad, a 7th century Arab religious and political figure and his personally demonstrated examples throughout his lifetime (collected through narration of his companions in the volumes of Hadith) for implementing them. For other meanings, including people named 'Islam', see Islam (disambiguation).