the script

Whereas English is written with
A a B b C c D d E e
F f G g H h I i J j
K k L l M m N n O o
P p Q q R r S s T t
U u V v W x , ; . :
! ? " - 1 2 3 4 5 6
7 8 9 0 (  ) [  ] /  \
% & # ' + * ~ ^ { }
(80 chars)
the first qurʾān manuscripts just have
  ا   ٮ‍   ح‍ د ر و  ه‍ ط ك‍ ل‍
م‍ س‍ ص‍ ع‍ ڡ‍ ڡ ٯ ع ص س
* م ل ك ‌ـه‌ ح ٮ ں ى لا
(30 chars)

Most people know that the earliest manuscripts
do have few diacritical dots, no ḥamza sign, no numerals,
no shadda, no hyphen, colon, just an end of aya sign,
but hardly anybody is aware of two facts:

There is no space between words.
{Th. Bauer is wrong ("Words are set apart by greater spaces" in Peter T. Daniel, ed. p. 559).}
There is no hyphenation: end of line is insignificant.

Start letters and End letters are distinct letters
(although standing for the same sound, they carry a different meaning), whereas Start and Middle forms, End and Iso forms are "just" a con­se­quence of the pre­ceding letter.
As "conserva­tive, liberals, god" are different from "Con­servative, Liberals, God"
= A and a are not the same letter
ح‍ and ح are not the same letter
Just as capital letters carry a meaning (person, majesty, name, start of a sentence ‒ in German: noun),
End (resp. Iso) carries the meaning: "end of the word".

Therefore there was no "space bet­ween words" ‒ or was it the other way round?
And because there is no End-waw (and because two alifs NEVER occur WITH­IN a word),
after waw at the end of a word an alif was added: the word border runs bet­ween the two alifs.
Lakhdar-Ghazal saw a core letter and end markers:
ح ع م
ٮ ل ى
س ص ں
That does not work for all letters and not for all calligraphic styles.
Unicode sees colon, space, Non-Joiner as triggering the end form of ONE letter.
That is clearly wrong for the early manuscripts.

Bauer's "each letter may occur in four different positions: initial, medial, final, and isolated" is a truism, but it shows, that he noticed that the common statement "each letter has four forms/gra­phic shapes" is untenable, both because many have only one form (in type­writer script), and many have more than twenty (in "high" naskhi).

Not trivial: "the common designation of the Arabic script as "con­sonantal" is in­correct, since the long vowels are re­presented but con­sonant gemina­tion is not." (Bauer in Daniel p.561) ‒ although not ALL long vowels are represented (as Bauer knows of course), and some short vowels are re­presented and diph­thongs as well. ‒­