The first to put dots in the Arabic language is Abu Al-Aswad Al-Du'ali, who is the founder of grammar. He only put dots to be a sign of vowels in the language, so the dot from the top indicates the fatha and the bottom indicates the kasra, and if there are two dots, it indicates the dhammah.

He drew these marks in red ink and used to say to his scribe: “Take red dye. If you see me opening my lips to write the letter, drop one at the top. If it breaks, drop one at the bottom. If you join it, put the dot in front of the letter. If I follow any of these movements, dot two dots.” He dictated it. The Holy Qur’an was complete in this way until he reached the end of the Qur’an, then he began to review it again.”

The method of Abu Al-Aswad Al-Du'ali spread, but only in the Qur’an and was not circulated in newspapers or books. Writing continued in this form until “Al-Khalil bin Ahmad Al-Farahidi” came in the second century AH. He set a more precise setting than that of Abu Al-Aswad Al-Du’ali and made the dots a small thousand. Slanting is an indication of the fatha, and placing a small yā’ under the letter is an indication of the kasra, and placing a small waw above the letter is an indication of the ḍamma. In the case of tanween, the letter is placed twice, and he has great credit for placing the hamza and stress in the Arabic language. He also added the bound ta’, the neglected alif, and the shortened alif.