The Uyghur or Uighur language (ər/ئۇيغۇر تىلى, Уйғур тили, Uyghur tili, Uyƣur tili or ئۇيغۇرچە, Уйғурчә, Uyghurche, Uyƣurqə), formerly known as Eastern Turki, is a Turkic language with 10 to 15 million speakers, spoken primarily by the Uyghur people in the Xinjiang Uyghur Autonomous Region of Western China. Significant communities of Uyghur-speakers are located in Kazakhstan, Kyrgyzstan and Uzbekistan, and various other countries have Uyghur-speaking expatriate communities. Uyghur is an official language of the Xinjiang Uyghur Autonomous Region, and is widely used in both social and official spheres, as well as in print, radio, and television, and is used as a common language by other ethnic minorities in Xinjiang.
The modified Arabic-derived writing system is the most common and the only standard in China, although other writing systems are used for auxiliary and historical purposes. Unlike most Arabic-derived scripts, the Uyghur Arabic alphabet has mandatory marking of all vowels due to modifications to the original Perso-Arabic script made in the 20th century. Two Latin and one Cyrillic alphabet are also used, though to a much lesser extent. The Arabic and Latin alphabets both have 32 characters.
Robert Barkley Shaw wrote, "In the Turkish of Káshghar and Yarkand (which some European linguists have called Uïghur, a name unknown to the inhabitants of those towns, who know their tongue simply as Túrki), ... This would seem in many case to be a misnomer as applied to the modem language of Kashghar".Sven Hedin wrote, "In these cases it would be particularly inappropriate to normalize to the East Turkish literary language, because by so doing one would obliterate traces of national elements which have no immediate connection with the Kaschgar Turks, but on the contrary are possibly derived from the ancient Uigurs".
Probably around 1077, a scholar of the Turkic languages, Mahmud al-Kashgari from Kashgar in modern-day Xinjiang, published a Turkic language dictionary and description of the geographic distribution of many Turkic languages, Dīwān ul-Lughat al-Turk (English: Compendium of the Turkic Dialects; Uyghur: تۈركى تىللار دىۋانىTürki Tillar Diwani). The book, described by scholars as an "extraordinary work," documents the rich literary tradition of Turkic languages; it contains folk tales (including descriptions of the functions of shamans) and didactic poetry (propounding "moral standards and good behaviour"), besides poems and poetry cycles on topics such as hunting and love, and numerous other language materials. Other Kara-Khanid writers wrote works in the Turki Karluk Khaqani language. Yusuf Khass Hajib wrote the Kutadgu Bilig. Ahmad bin Mahmud Yukenaki (Ahmed bin Mahmud Yükneki) (Ahmet ibn Mahmut Yükneki) (Yazan Edib Ahmed b. Mahmud Yükneki) (w:tr:Edip Ahmet Yükneki) wrote the
Hibat al-ḥaqāyiq (هبة الحقايق) (Hibet-ül hakayik) (Hibet ül-hakayık) (Hibbetü'l-Hakaik) (Atebetüʼl-hakayik) (w:tr:Atabetü'l-Hakayık).
Modern Uyghur religious literature includes the Taẕkirah, biographies of Islamic religious figures and saints. The Taẕkirah is a genre of literature written about Sufi Muslim saints in Altishahr. Written sometime in the period between 1700 and 1849, the Chagatai language (modern Uyghur) Taẕkirah of the Four Sacrificed Imams provides an account of the Muslim Karakhanid war against the Khotanese Buddhists, containing a story about Imams, from Mada'in city (possibly in modern-day Iraq) came 4 Imams who travelled to help the Islamic conquest of Khotan, Yarkand, and Kashgar by Yusuf Qadir Khan, the Qarakhanid leader. The shrines of Sufi Saints are revered in Altishahr as one of Islam's essential components and the tazkirah literature reinforced the sacredness of the shrines. Anyone who does not believe in the stories of the saints is guaranteed hellfire by the tazkirahs. It is written, "And those who doubt Their Holinesses the Imams will leave this world without faith, and on Judgement Day their faces will be black ..." in the Tazkirah of the Four Sacrificed Imams. Shaw translated extracts from the Tazkiratu'l-Bughra on the Muslim Turki war against the "infidel" Khotan. The Turki-language Tadhkirah i Khwajagan was written by M. Sadiq Kashghari. Historical works like the Tārīkh-i amniyya and Tārīkh-i ḥamīdi were written by Musa Sayrami.
The Bible was translated into the Kashgari dialect of Turki (Uyghur).
The historical term "Uyghur" was appropriated for the language that had been known as Eastern Turki by government officials in the Soviet Union in 1922 and in Xinjiang in 1934.Sergey Malov was behind the idea of renaming Turki to Uyghurs. The use of the term Uyghur has led to anachronisms when describing the history of the people. In one of his books the term Uyghur was deliberately not used by James Millward. The name Khāqāniyya was given to the Qarluks who inhabited Kāshghar and Bālāsāghūn, the inhabitants were not Uighur, but their language has been retroactively labelled as Uighur by scholars. The Qarakhanids called their own language the "Turk" or "Kashgar" language, and did not use Uighur to describe their own language, Uighur was used to describe the language of non-Muslims but Chinese scholars have anachronistically called a Qarakhanid work written by Kashgari as "Uighur". The name "Altishahri-Jungharian Uyghur" was used by the Soviet educated Uyghur Qadir Haji in 1927.