Damma

The Arabic script has numerous diacritics, including i'jam ⟨إِعْجَام⟩ (i‘jām, consonant pointing), and tashkil ⟨تَشْكِيل⟩ (tashkīl, supplementary diacritics). The latter include the ḥarakāt ⟨حَرَكَات⟩ (vowel marks; singular: ḥarakah ⟨حَرَكَة⟩).

The Arabic script is an impure abjad, where short consonants and long vowels are represented by letters but short vowels and consonant length are not generally indicated in writing. Tashkīl is optional to represent missing vowels and consonant length. Modern Arabic is also written without consonant pointing, but some books are written with consonant pointing such as books for Arabic learners and children's books.

The literal meaning of tashkīl is 'forming'. As the normal Arabic text does not provide enough information about the correct pronunciation, the main purpose of tashkīl (and ḥarakāt) is to provide a phonetic guide or a phonetic aid; i.e. show the correct pronunciation. It serves the same purpose as furigana (also called "ruby") in Japanese or pinyin or zhuyin in Mandarin Chinese for children who are learning to read or foreign learners.

The bulk of Arabic script is written without ḥarakāt (or short vowels). However, they are commonly used in texts that demand strict adherence to exact wording. This is true, primarily, of the Qur'an ⟨الْقُرْآن⟩ (al-Qur’ān) and poetry. It is also quite common to add ḥarakāt to hadiths ⟨الْحَدِيث⟩ (al-ḥadīth; plural: aḥādīth) and the Bible. Another use is in children's literature. Moreover, ḥarakāt are used in ordinary texts in individual words when an ambiguity of pronunciation cannot easily be resolved from context alone. Arabic dictionaries with vowel marks provide information about the correct pronunciation to both native and foreign Arabic speakers. In art and calligraphy, ḥarakāt might be used simply because their writing is considered aesthetically pleasing.

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