Literally “the recitation”; also called al-qurān al-karīm “The Noble Qur’an”; is the central religious text of Islam. Muslims believe the Qur’an, in its original Arabic, to be the literal word of God that was revealed to Muhammad over a period of twenty-three years until his death, and believe it to be God’s final revelation to humanity. The Qur’anic verses were originally memorized by Muhammad’s companions as Muhammad spoke them, with some being written down by one or more companions on whatever was at hand, from stones to pieces of bark. Compilations of the Qur’an began under the Caliph Umar, but it was Uthman who decided upon a definitive copy and destroyed all other versions that had resulted from the differences of pronunciation of the words.