official language of the Republic of India, a central Indo-Aryan language (Indo-Aryan languages) claimed as a mother tongue by some 180,000,000 speakers in India. There are also significant numbers of Hindi speakers outside of India, including nearly 1,000,000 in South Africa, 700,000 in Mauritius, 350,000 in Bangladesh, 235,000 in Yemen, and 150,000 in Uganda. Many more hundreds of thousands speak Hindi as a second language. Literary Hindi, written in the Devanagari (Devanāgarī) script, shows a strong influence of Sanskrit (Sanskrit language) as a source for borrowings; it is based on the Khari Boli dialect, to the north and east of Delhi. Also commonly treated as dialects of Hindi are Braj Bhasa (Braj Bhasa language), which was an important literary medium from the 15th to the 17th century; Awadhi, also a literary medium; and Bagheli, Chattisgarhi, Bundeli, and Kanauji.

Hindi has a much simpler inflectional (inflection) system than does Sanskrit, although the literary language uses a great number of Sanskrit forms. Nouns and pronouns have lost the full declension in eight cases of Sanskrit and instead make use of postpositions—small words attached to the end of nouns and functioning much like English prepositions. There are only two genders, masculine and feminine, whereas Gujarati and Marathi retain three. Verbs also are much reduced in inflectional complexity, with only the present and future indicative forms fully conjugated; other constructions are based on participial forms.