Once the standard text had been established, several copies were made and sent to major cities in the Islamic domain, specifically Damascus, al-Basrah, al-Kufah, and perhaps others.
Although there are variations in detail, for example, in the list of names of those who served on ‘Uthmans commission and in the list of cities to which copies were sent, this basic outline is not in dispute within the Muslim world.
Oral recitation nevertheless remained the preferred mode of transmission, and, as time passed, variant versions of the text proliferated - the kind of organic change that is endemic to an oral tradition. In addition, because of the nature of the early Arabic script, in which short vowels were not indicated and consonants of similar form were only sometimes distinguished by pointing, writing, too, was subject to misunderstanding, copyists error, and change over time.
In the early tenth century, at Baghdad, Abu Bakr Ibn Mujahid (d. 324 / 936) succeeded in reducing the number of acceptable readings to the seven that were predominant in the main Muslim centers of the time: al-Madinah, Makkah, Damascus, al-Basrah, and al-Kufah.