Urdu (اردو) is the national language and lingua franca of Pakistan, and an official language of five Indian states and one of the 22 scheduled languages in the Constitution of India. this is associated with the Muslim religion. The population of Hindi-Urdu speakers is the fourth largest of the languages of the world, after Mandarin Chinese, English and Spanish. Urdu has a vocabulary rich in words with and Middle Eastern origins. The language's Indo-Aryan base has been enriched by borrowing from Persian and Arabic. There are also a smaller number of borrowings from Chagatai, Portuguese, and more recently English. Many of the words of Arabic origin have been adopted through Persian and have different pronunciations and nuances of meaning and usage than they do in Arabic. Urdu is written right-to left in an extension of the Persian alphabet, which is itself an extension of the Arabic alphabet.