The original manuscript of the Quran does not have the signs indicating the vowels in Arabic script.
In addition to the diacritical marks, there are other forms of vocalization marks that change the pronunciation and meaning of a given word. These marks include Damma, Fathha, kassra, shadda, scoon, madda, etc. They are put above or below the letter to affect its pronunciation.
The Arabs did not require the vowel signs and diacritical marks for correct pronunciation of the Quran since it was their mother tongue. For Muslims of non-Arab origin, however, it was difficult to recite the Quran correctly without the vowels. These marks were introduced into the Quranic script during the time of the fifth ‘Umayyad’ Caliph, Malik-ar-Marwan (66-86 Hijri/685-705 C.E.) and during the governorship of Al-Hajaj in Iraq.
Some people argue that the present copy of the Quran that we have along with the vowels and the diacritical marks is not the same original Quran that was present at the Prophet’s time. But they fail to realize that the word ‘Quran’ means a recitation. Therefore, the preservation of the recitation of the Quran is important, irrespective of whether the script is different or whether it contains vowels. If the pronunciation and the Arabic is the same, naturally, the meaning remains the same too.
(ئ ؤ إ أ and stand alone ء) hamza: indicates a glottal stop.
(ــًــٍــٌـ) tanwīn (تنوين) symbols: Serve a grammatical role in Arabic. The sign ـً is most commonly written in combination with alif, e.g. ـًا.
(ــّـ) shadda: Gemination (doubling) of consonants.
(ٱ) waṣla: Comes most commonly at the beginning of a word. Indicates a type of hamza that is pronounced only when the letter is read at the beginning of the talk.
(آ) madda: A written replacement for a hamza that is followed by an alif, i.e. (ءا). Read as a glottal stop followed by a long /aː/, e.g. ءاداب، ءاية، قرءان، مرءاة are written out respectively as آداب، آية، قرآن، مرآة. This writing rule does not apply when the alif that follows a hamza is not a part of the stem of the word, e.g. نتوءات is not written out as نتوآت as the stem نتوء does not have an alif that follows its hamza.
(ــٰـ) superscript alif (also “short” or “dagger alif”: A replacement for an original alif that is dropped in the writing out of some rare words, e.g. لاكن is not written out with the original alif found in the word pronunciation, instead it is written out as لٰكن.
ḥarakāt (In Arabic: حركات also called تشكيل tashkīl):
(ــَـ) fatḥa (a)
(ــِـ) kasra (i)
(ــُـ) ḍamma (u)
(ــْـ) sukūn (no vowel)
The ḥarakāt or vowel points serve two purposes:
They serve as a phonetic guide. They indicate the presence of short vowels (fatḥa, kasra, or ḍamma) or their absence (sukūn).
At the last letter of a word, the vowel point reflects the inflection case or conjugation mood.
For nouns, The ḍamma is for the nominative, fatḥa for the accusative, and kasra for the genitive.
For verbs, the ḍamma is for the imperfective, fatḥa for the perfective, and the sukūn is for verbs in the imperative or jussive moods.
Vowel points or tashkīl should not be confused with consonant points or iʿjam (إعجام) – one, two or three dots written above or below a consonant to distinguish between letters of the same or similar form.