Urdu (اردو‎) is the national language (قومی زبان‎), lingua franca and one of two official languages of Pakistan (the other currently being English). Although only about 8% of Pakistanis speak it as their first language, it is widely spoken and understood as a second language by the vast majority of Pakistanis and is being adopted increasingly as a first language by urbanized Pakistanis. It was introduced as the lingua franca upon the capitulation and annexation of Sindh (1843) and Punjab (1849) with the subsequent ban on the use of Persian. According to the linguistic historian Tariq Rahman, however, the oldest name of what is now called Urdu is Hindustani or Hindvi and it existed in some form at least from the 14th century if not earlier (Rahman 2011). It was probably the Indo-Aryan language of the area around Delhi that absorbed words of Persian, Arabic, and Chagatai (a Turkic language)—in a process like the one that created modern English. This language, according to Rahman, is the ancestor of both modern Hindi and Urdu. These became two distinct varieties when Urdu was first Persianized in the 18th century and then Hindi was Sanskritized from 1802 onwards.
The name Urdu is a short form of 'Zuban-e-Urdu-e-Mualla' i.e. language of the exalted city. In India the term Urdu, although it means 'military camp' in most Turkic languages, was used for the capital city of the king. In other words, the language of the king's capital was a Persianized form of the language known only by its previous and currently less common name Hindustani. This was shortened to 'Urdu' and this term was used for the first time in written records by the poet Mushafi in 1780 (Rahman 2011: 49). It is widely used, both formally and informally, for personal letters as well as public literature, in the literary sphere and in the popular media. It is a required subject of study in all primary and secondary schools. It is the first language of most Muhajirs (Muslim refugees who fled from different parts of India after independence of Pakistan in 1947), who form nearly 8% of Pakistan's population, and is an acquired second language for the rest. As Pakistan's national language, Urdu has been promoted to promote national unity. It is written with a modified form of the Perso-Arabic alphabet—usually in Nastaliq script.