Naskh, whose name derives from an Arabic root meaning to copy, is the rounded, legible cursive script that displaced Kufic as the standard hand for copying the Qur'an from roughly the tenth and eleventh centuries, and its rise tracks a real historical shift in how the Muslim community related to its scripture in written form, as growing numbers of readers needed a script that could be read fluently by someone not already carrying the text in memory, a job Kufic's austere, sparsely marked letterforms did poorly.
Naskh's classical proportions owe much to the systematic reform of Arabic scripts associated with the tenth century vizier and calligrapher Ibn Muqla, whose geometric method of relating letterforms to a standard dot unit and circle brought a rigor and reproducibility to Arabic calligraphy that later masters, including Ibn al-Bawwab and Yaqut al-Musta'simi, refined further across the following centuries, establishing naskh and its related scripts as a disciplined art with defined rules rather than simply a matter of individual scribal habit. The script's clarity made it the natural choice not only for Qur'ans but for the huge body of scholarly, literary and administrative writing that Islamic civilisation produced across the medieval period, and naskh remains, in its modern typographic descendants, the standard printed form of Arabic script used in books, newspapers and digital text across the Arabic speaking world today.