Urdu is an Indo-Aryan language of the Indo-Iranian branch, belonging to Indo-European family of languages. It developed in South Asia during the Delhi Sultanate and Mughal Empire (1526 - 1858 AD). It is the national language of Pakistan as well as one of the 23 official languages of India. This language is conventionally written in Nastaliq calligraphy style of the Perso-Arabic script and draws vocabulary more heavily from Persian and Arabic. Linguists, nonetheless, consider Urdu and Hindi to be two standardized forms of the same language, which is popularly known as Hindustani.