The various Turkic languages have been written in a number of different alphabets, including Cyrillic, Arabic, Greek, Latin and other writing systems. The earliest known Turkic alphabet is the Orkhon script. When Turks adopted Islam, they began to use Arabic script for their languages, especially under the Kara-Khanids. Though the Seljuks used Persian as their official language, in the late Seljuk period, Turkish began to be written again in Anatolia in the nascent Ottoman state. The Ottoman Turkish alphabet is a Turkish form of the Perso-Arabic script. Well suited to writing Arabic and Persian borrowings, it was poorly suited to native Turkish words. When it came to consonants, Arabic has several consonants that do not exist in Turkish, making several Arabic letters superfluous except for Arabic loanwords; conversely, a few letters had to be invented to write letters in Persian and Turkish that Arabic did not have. In the case of vowels, Turkish contains eight different short vowels and no long ones, whereas Arabic have three short and three long vowels; further complicating matters was that in the Arabic script, only long vowels are usually expressed. Still, Turkic languages such as Azerbaijani and Uzbek continue to be written using Arabic script in Iran, Afghanistan, and Iraq. The introduction of the telegraph and the printing press in the 19th century exposed further weaknesses in the Arabic script. . The first 3 lines in Ottoman Turkish Arabic script give the date in the Rumi, 20 Teşrin-i Evvel 1311, and Islamic, 14 Jumādā al-Ūlā 1313, calendars; the Julian and Gregorian dates appear below. Some Turkish reformers promoted the Latin script well before Atatürk's reforms. In 1862, during an earlier period of reform, the statesman Münuf Pasha advocated a reform of the alphabet. At the start of the 20th century, similar proposals were made by several writers associated with the Young Turk movement, including Hüseyin Cahit, Abdullah Cevdet and Celâl Nuri. The issue was raised again in 1923 during the İzmir Economic Congress of the new Turkish Republic, sparking a public debate that was to continue for several years. A move away from the Arabic script was strongly opposed by conservative and religious elements. It was argued that Romanization of the script would detach Turkey from the wider Islamic world, substituting a foreign concept of national identity for the confessional community. Others opposed Romanization on practical grounds, as was no suitable adaptation of the Latin script that could be used for Turkish phonemes. Some suggested that a better alternative might be to modify the Arabic script to introduce extra characters for better representing Turkish vowels. In 1926, the Turkic republics of the Soviet Union adopted the Latin script, giving a major boost to reformers in Turkey.
Ottoman Turkish script was replaced by the Latin-based new Turkish alphabet. Its use became compulsory in all public communications in 1929. The change was formalized by the Law on the Adoption and Implementation of the Turkish Alphabet, passed on November 1, 1928, and effective on January 1, 1929.
As with Arabic and Persian, texts in the Ottoman Turkish alphabet are written right to left. The appearance of a letter changes depending on its position in a word:
medial ; and
Some letters cannot be joined to the left and so do not possess separate medial and initial forms. In medial position, the final form is used. In initial position, the isolated form is used.
The orthography of Ottoman Turkish is complex, as many Turkish sounds can be written with several different letters. For example, the phoneme /s/ can be written as,, or. Conversely, some letters have more than one value: k may be /k/, /ɡ/, /n/, /j/, or /ː/, and vowels are written ambiguously or not at all. For example, the text kwrk can be read as /ɡevrek/ 'biscuit', /kyrk/ 'fur', /kyrek/ 'shovel', /kœryk/ 'bellows', /ɡœrek/ 'view', which in modern orthography are written gevrek, kürk, kürek, körük, görek. Arabic and Persian borrowings are written in their original orthography: sabit 'firm' is written as s̱’bt, with s̱ representing /s/, and ’ representing /aː/ as in Arabic but with no indication of the short /i/. The letters ث ح ذ ض ظ ع are found only in borrowings from Arabic; ژ is only in borrowings from Persian and French. Although the Arabic vowel points can be used s̱a’bit, they are generally found only in dictionaries and didactic works, as in Arabic and Persian, and they still do not identify vowel sounds unambiguously. Consonant letters are classified in three series, based on vowel harmony: soft, hard, and neutral. The soft consonant letters, ت س ك گ ه, are found in front vowel contexts; the hard, ح خ ص ض ط ظ ع غ ق, in back vowel contexts; and the neutral, ب پ ث ج چ د ذ ر ز ژ ش ف ل م ن, in either. In Perso-Arabic borrowings, the vowel used in Turkish depends on the softness of the consonant. Thus, klb 'dog' is /kelb/, while ḳlb 'heart' is /kalb/. Conversely, in Turkish words, the choice of consonant reflects the native vowel.
In Turkish words, vowels are sometimes written using the vowel letters as the second letter of a syllable: elif for /a/; ye for /i/, /ɯ/; vav for /o/, /œ/, /u/, /y/; he for /a/, /e/. The corresponding harakat are there: ustun for /a/, /e/; esre for /ɯ/, /i/; ötre for /o/, /œ/, /u/, /y/. The names of the harakat are also used for the corresponding vowels.
ا elif ه he
Other scripts were sometimes used by non-Muslims to write Ottoman Turkish since the Arabic alphabet was identified with Islam. The first novel to be written in the Ottoman Empire was Akabi, which was written in the Armenian script by Vartan Pasha. Similarly, when the Armenian Duzian family managed the Ottoman mint during the reign of SultanAbdülmecid I, they kept records in Ottoman Turkish but used the Armenian script. The Greek alphabet and the Rashi script of Hebrew were used by Greeks and Jews for Ottoman. Greek-speaking Muslims would write Greek using the Ottoman Turkish script.