Quranic Orthography
To ensure correct reading of the written texts of the Qurʾān, particularly for those coming after the first generation of Muslims, steps were taken gradually to improve the orthography. This started by introducing dots to indicate different vowels and nunation and these were put in different coloured ink from that of the text. There were also dots to distinguish between consonants of similar shape. This work was carried out chiefly by three men: Abu'l Aswad ad-Du'alî (d. 69 / 688), Naṣr Ibn ʿĀṣim (d. 89 / 707) and Yaḥya Ibn Yaʿmur (d.129 /746). Understandably there was some opposition at first to adding anything to the way the Qurʾān was written. Ibn ʿUmar (73/692) disliked the dotting; others welcomed it, clearly because it was, in fact, doing no more than ensuring proper reading of the Qurʾān as received from the Prophet, and this view was accepted by the majority of Muslims throughout the different parts of the Muslim world, from the time of the tābiʿūn. The people of Madinah were reported to have used red dots for vowels - tanwīn, tashdīd, takhfīf, sukīn, waṣl and madd and yellow dots for the hamzas in particular. Naqt (placing dots on the rasm), became a separate subject of study with many books written on it.
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