Most people think that there is ONE way to write the qurʾān, that if we leave the different qiraʾāt aside and ignore the style of writing, all copies of the qurʾān are the same.
And that they are written alright.
The opposite is true:
there are many different qurʾanic „ortho“graphies and none is ortho/right.
b, k, l, m, n, t … are fine. Paleo-Linguists argue about ض ص ط ظ
But for modern readers only the vowels are problematic: short and long vowells.
Principally there are two systems:
an Indian system with seven vowel signs (a ā i ī u ū x)
an African System which needs vowel sign plus thr corresponding letter for long vowells.
The African system is today common in the Arab world. When here is no lengthening letter (waw, yāʾ, alif) after ḍamma, kasra, fatḥa, a small letter is added. When the rules of prosody require an „ī“ although no yāʾ is in the rasm, a small ya baree is added.
But when the rules of prosody require a (long, a wriiten) yāʾ to be shortended,
that is not reflected in the text.
Indians, Turks, Persians, Indonesians are not happy with this. The Arab attitude „everybody knows that these letters do not lengthen the vowel at these places“ sounds arrogant in non-Arab hears.
And when it is not a general rule, but a local one = when a vowell is short because it must rhyme with lines before and after, this IS reflected in the Arab-African text. So why not: all the time?
Here you see words from an Indian manuscript in which ONLY the vowel SIGNS count, the „lengthening“ vowels are IGNORED — al-farīqaini in the last line has jazm above the yāʾ because in the diphthong yāʾ is NOT silent — the underlying rule being: letter without ANY sign are ignored.
The modern Indian system (here black on white background) is a mix of the old consistent system and the African one: when the CORRESPONDING letter follows a vowel sign, the SHORT vowel sign is used (as in Africa), only when there is a different letter or no „lengthening“ letter at all, the long vowel sign is used.
Welt des Islam 