Persian and Urdu
The Persian language historically influenced many of the modern languages and dialects of the Middle East, Central Asia, Eastern Europe, and South Asia including the standard register Urdu, the national language of Pakistan.
Following the Turko-Persian Ghaznavid conquest of South Asia, the speech based in Delhi's Khariboli dialect and other dialects of South Asia received a large influx of Persian, Chagatai and Arabic vocabulary. The subsequent Turko-Afghan Delhi Sultanate gave way for a further continuation of this. The basis in general for the introduction of the Persian language into the subcontinent was set, from its earliest days, by various Persianized Central Asian Turkic and Afghan dynasties.
This lexically diverse register of language, emerged in the northern subcontinent, was commonly called Zaban-e Urdu-e Mualla ('language of the exalted city') and eventually replaced Persian, the court language, and its name was shortened to just "Urdu". It grew from the interaction of Persian and Turkic-speaking Muslim soldiers and the native Indians. Under Persian influence from the state, the Persian Nastaʿlīq script was adopted, with additional figures added to accommodate the Indo-Aryan phonetic system.
Unlike Persian, which is an Iranian language, Urdu is a variant of an Indo-Aryan language, written in the Perso-Arabic script, and contains literary conventions and specialized vocabulary largely from Persian. Some grammatical elements peculiar to Persian, such as the enclitic ezāfe and the use of pen-names, were readily absorbed into Urdu literature both in the religious and secular spheres.
Modern Persian has three major variants: Western Persian (spoken primarily in Iran, known by its native speakers as "Farsi", the literal Persian word for itself), Dari (spoken as a lingua franca by a large majority of Afghans) and Tajik (spoken by the Tajiks of Tajikistan). These variants are almost entirely mutually intelligible with one another.
 Both Hindi and Urdu are almost entirely mutually intelligible with one another, but have somewhat distinct vocabulary and minor terminological differences. Another major difference is their writing systems are entirely different, with Hindi using Devanagari and Urdu using the Nastaʿlīq script.
Hindustani gained distinction in literary and cultural spheres in South Asia because of its role as a lingua franca in the subcontinent as a result of the large number of speakers the language has, both as a first and second language. A prominent cross-over writer was Amir Khusrow, whose Persian and Urdu couplets are to this day read in South Asia. Muhammad Iqbal was also a prominent South Asian writer who wrote in Persian and Urdu.
Urdu scholars in Persian literature
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