EDIT Writing system Arabic is the script used to write the Arabic language. It is a cursive script, written with connected characters, vertically from right to left. There is no distinction between upper and lower case, words are written separately. Numbers are written left to right. Most characters exist in several shapes, depending on whether they are used by themselves, at the beginning of a word, within a word or at its end (isolated, initial, medial or final). Six characters only exist in an isolated or final form and don\'t connect with the following letter that then must be written in its isolated or initial shape even if it occurs in the middle of a word.

The Arabic alphabet contains 28 main letters, all of them consonants. Vowels are usually not indicated within words, it is a matter of experience and context to decide which word has actually been written. Only in the Qur’an and sometimes in poetry or texts meant for teaching vowels are indicated.

There are three actual characters representing long vowels:
Alef (Arabic Letter Alef, U+0627), Waw (Arabic Letter Waw, U+0648) and Alef Maksura (Arabic Letter Alef Maksura, U+0649). This character also exists in two modified forms: Arabic Letter Yeh U+064A and Arabic letter Farsi Yeh U+06CC.

There are also three diacritics for the indication of short vowels: Fatha (Arabic Fatha, U+064E), Kasra (Arabic Kasra, U+0650) and Damma (Arabic Damma, U+064F). They are positioned above or below the consonant preceding the vowel. When they are used a text is considered »fully vocalized«.

Other important diacritical characters are Shadda (Arabic Shadda, U+0651) which marks the doubling of a consonant, and Hamza (Arabic Letter Hamza, U+0621) which usually only occurs in combination with an Alif and indicates that the Alif does not stand for a vowel but marks a glottal stop. The third important diacritic is Sukun (Arabic Sukun, U+0652). It is needed to show that a syllable is closed (e.g. not ended by a consonant), it marks the absence of a vowel after the base consonant. In some Qur’ans it also marks a long vowel as ignored.

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EDIT History The Arabic Script evolved from the Nabataean Aramaic script and has been used since the 4th century. In the 7th century new characters were created by adding dots to existing characters because Aramaic has less consonants than Arabic. Diacritics indicating short vowels were also added, mainly to ensure the correct loud reading of the Qur’an.

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EDIT Languages that are or used to be written with the Arabic script :
Afrikaans, Albanian, Arabic, Azeri, Baluchi, Berber, Bashkir, Belarussian, Bosnian, Chaghatai, Chechen, Chinese, Comorian, Fulani, Hausa, Hebrew, Kashmiri, Kazakh, Kurdish, Kyrghyz, Malay, Mandinka, Morisco, Mozarabic, Nubian, Pashto, Persian/Farsi, Punjabi, Sanskrit, Sindhi, Somali, Songhay, Swahili, Tamazight, Tatar, Turkish, Turkmen, Urdu, Uyghur, Uzbek and Wolof.

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