Urdu, or more precisely Standard Urdu, is a South Asian language in the Indo-Aryan branch in the Indo-European family of languages. It is the national language and lingua franca of Pakistan. It is also an official language of five Indian states and one of the 22 scheduled languages in the Constitution of India. Based on the Khariboli dialect of Delhi, Urdu developed under the influence of Persian, Arabic, and Turkic languages over the course of almost 900 years. It originated in the region of Uttar Pradesh in the Indian subcontinent during the Delhi Sultanate (1206–1527), and continued to develop under the Mughal Empire (1526–1858). Urdu is mutually intelligible with Standard Hindi spoken in India. Both languages share the same Indo-Aryan base, and are so similar in basic structure, grammar and to a large extent vocabulary and phonology, that they appear to be one language. The combined population of Urdu and Standard Hindi speakers is the fourth largest in the world. Mughals hailed from the Barlas tribe which was of Mongol origin, the tribe had embraced Turkic and Persian culture, and resided in Turkestan and Khorasan. Their mother tongue was the Chaghatai language (known to them as Turkī, \Turkic\) and they were equally at home in Persian, the lingua franca of the Timurid elite. But after their arrival in the Indian subcontinent, the need to communicate with local inhabitants led to use of Indo-Aryan languages written in the Persian alphabet, with some literary conventions and vocabulary retained from Persian and Turkic; this eventually became a new standard called Hindustani, which is the direct predecessor of Urdu.