The Turki language is a Turkic literary language active from the 13th to the 19th centuries, used by different (predominantly but not exclusively) Turkic peoples. The Turki language developed on the Karluk (Karluk-Khorezm languages) basis, which was a result of interaction of the Karakhanid language with the local Turkic languages (gradual replacement of d-type language with a j-type language). The Karakhanid Karluk language was adapted for a cycle of works in Khorezm, where it was enriched by Oguz and Kipchak elements and turned into one of the medieval Türkic languages. With the Turki were created Qutba's poem Khosrow and Shirin (1338), Khwarizmi Muhabbat-name (1353), Sutro Sarai Gulistan bi-t-Türki (1391), Mahmud al-Bukhari theological and didactic work Nahj al faradis (1358).
While there were several regional variations of the Turki, they were united by their commonality, predicated by
- a relative proximity of Turkic languages and active cultural and linguistic contacts between different Turkic areals which all professed Islam;
- a use of Arabic alphabet, where the graphics does not fully reflect vowels, and therefore the same word in different regions could be read differently;
- an abundance of Arab and Persian loanwords 
Regional variations of the Turki and Turkic linguistic areals under its influence:
- Middle Asia (Karluk-Khwarezmian) – Karluk-Khwarezmian (Uzbek, Modern Uyghur);
- Kipchak (Aral-Caspian) – Kipchak Nogai (Karakalpak, Kazakh, Uzbek Kypchak), Kyrgyz-Kipchak (Kyrgyz);
- Eastern Oguz – Eastern Oguz (Turkmen, Turkmen-Uzbek, Khorasani Turkic);
- Volga – Urals (Tatar, Bashkir);
- North Caucasus – Kypchak (Kumyk, Karachay-Balkar), Kypchak Oguz (Northern Seljuk) – Northern Azeri, Kypchak Nogai (Nogai);
- Asia Minor – South Oguz-Seljuk (Turkish);
- Crimean – Crimean Tatar areals Oguz-Seljuk, Kypchak-Bulgar, Kypchak Nogai depending on the dialect.
A number of Turkic languages did not partake in the development of the Turki literary tradition, and were either unaffected by the common trends carried by the Turki, or affected only indirectly through the neighboring languages that were impacted by the Turki. The languages not affected directly were culturally separated from the Islamic influence by religious affiliations or geographical isolation. Among such nations were Chuvashes, Gagauzes, Hungarian Kipchaks, Bulgars, Szeklers, and other Hungarian Turkic subdivisions, western Tatars in Poland, Baltic states, Belarus, Russia and Ukraine, Siberian Turkic nations, modern Uigurs, nations that later formed Southern and Northern Altaians, and the Sakha people. The isolation of these people from the influence and innovations of the Turki facilitated preservation in their languages of the original forms and lexicons, now used for philological studies and comparative linguistics. The western European nations in the Christian sphere of influence were separated by religious and cultural barriers, and within the Christian sphere by different and frequently conflicting denominations and local linguistic barriers. The Siberian Türks from the beginning retained their independence from the Islamic influence, and largely preserved their Tengrian religion. The eastern Turkic nations fell under the influence of the Mongol Empire, and remained culturally affiliated with the Chingizid states after the fragmentation of the Mongol Empire.
In the international arena, Turki was an Arabic or Persian adjective formed from the noun "Turk", used by European writers in two rather different senses. Firstly, it is applied to tribes or languages which are Turkic as opposed to being Iranian or Semitic. Secondly, it is used as the special designation of the tribes and languages of Eastern Turkestan.
"Turki" as a word is also in common usage for variety of subjects related to Turks and in a widespread area. It could be used for the language spoken by Turks, could imply culture of Turks, Turkic descent and even dynasties. Its usage is also widespread in South Asia, Central Asia and Turkey. Lastly, the Turks being referred in the context of Turki are not necessarily from Turkey.
- M.Z. Zakiev, Tatars: problems of history and language, Kazan, 1995 (In Russian)
- E.R. Tenishev, Inter-national communication language of Altyn Orda Era, Kazan, 2000//Report at the round table (In Russian)
- ru:Язык тюрки
- M.Z. Zakiev, Ibid
- M.Z. Zakiev, Ibid