One tradition has it that the first complete compilation of the Qur'an was made during the rule of the first caliph, Abu Bakr. Zayd ibn Thabit, who had been one of Muhammad's secretaries, "gathered the Qur'an from various parchments and pieces of bone, and from the chests (i.e. the memories) of men." [Needs reference] This compilation was kept by Hafsa bint Umar, one of Muhammad's widows, as well as the daughter of Umar, the second caliph.
During the caliphate of Uthman ibn Affan, there were disputes about the recitation of the Qur'an. In response, Uthman decided to codify, standardize, and write down the text. Uthman is said to have commissioned a committee (including Zayd and several prominent members of Quraysh) to produce a standard copy of the text.
Some accounts say that this compilation was based on the text kept by Hafsa. Other stories say that Uthman made his compilation independently, Hafsa's text was brought forward, and the two texts were found to coincide perfectly. Still other accounts omit any reference to Hafsa.
Some Muslim scholars say that if the Qur'an had been collected by the order of a caliph, it would never have been relegated to the status of a keepsake for one of the prophet's widows. Possibly the story was invented to move the time of collection closer to Muhammad's death.
When the compilation was finished, sometime between 650 and 656 CE, Uthman sent out copies of it to the various corners of the Islamic empire. He ordered the destruction of all copies that differed from it.