Dotting and Vowelization

Dotting and vowelization passed through three stages:

1. In the first stage: Dots were used as syntactical marks. This was in the era of Mu`awiyah Ibn Abi Sufyan, who charged Abu Al-Aswad Al-Dualy to do it in order to prevent people from a faulty reading of the Quran.
2. In the second stage: Arabic letters were marked with different dotting to differentiate between them (e.g.:B, T,TH). This was in the time of Abdul-Malik Ibn Marawan, who charged Al-Hajjaj to do it. Al-Hajjaj, in his turn, charged Nasr Ibn Asem and Hayy Ibn Yaamor to accomplish it.
3. In the third stage: Complete vowel points (e.g. dammah, fathah, kasrah) were used, in the form we are using nowadays. This method was invented by Al-Khaleel Ibn Ahmed Al Faraheedi.