►II. WRITING SYSTEM & SOUNDS
►II.1. ORIGINS OF THE WRITING SYSTEM
Like many other ancient alphabets of Western Asia, Central Asia, and Southern Asia, the Arabic alphabet is in origin a modified version of the Aramaic alphabet. The pre-Classical Arabians had originally their independent alphabetic traditions (e.g. the Epigraphic South Arabian), but the Nabataeans (who were Aramized Arabs) introduced to pre-Classical Arabia a version of the Aramaic alphabet, and this Nabataean alphabet evolved into the (Classical) Arabic alphabet, which is still in use today. With the spread of Islam the Arabic alphabet has been adopted by many Muslim peoples to write their own languages.
Before the 7th century AD, the Arabic alphabet had only 18 symbols that represented 31 sounds (28 consonants and the three long vowels ā, ū, ī). The three short vowels a, u, i had no symbols to represent them in writing. In the 7th century AD, a system of dots (called ʔiʕǵȃmuṋ إِعْجَاْمٌ ) was introduced to indicate unambiguously all the consonants and vowels of Classical Arabic. Many modern Arabs believe that this system was invented by Abȗ ʔ·al-ʔAswadi ʔ·ad-Duʔaliyyu أَبُوْ الأَسْوَدِ الدُّؤَلِيُّ , a companion of the caliph ʕAliyy; but Western scholars believe this to be a false allegation invented by later philologists of the Classical Baṣra school of linguistics.
The initial system of dots was modified in the 8th century by the renowned linguist ʔ·Al-Xalȋlu bnu ʔAħmada ʔ·al-Farȃhȋdiyyu الْخَلِيْلُ بْنُ أَحْمَدَ الْفَرَاْهِيْدِيُّ . In the new system introduced by ʔ·Al-Xalȋl, the dots indicating the short vowels and geminate letters were replaced by diacritical marks that had the shapes of small Arabic letters placed above or below the letters. This system remains in use today with no substantial change.