Hindi is an Indo-European language spoken mainly in northern and central India, is the primary official language of the Union government of India. It is part of a dialect continuum of the Indic family, bounded on the northwest and west by Punjabi, Sindhi, Urdu, and Gujarati; on the south by Marathi; on the southeast by Oriya; on the east by Bengali; and on the north by Nepali. Hindi also refers to a standardized register of Hindustani termed khari boli, that emerged as the standard dialect of Hindi.

The grammatical description in this article concerns this standard Hindi. Hindi is often contrasted with Urdu, another standardized form of Hindustani that is the official language of Pakistan and also an official language in some parts of India. The primary differences between the two are that Standard Hindi is written in Devanagari and draws its vocabulary with words from Sanskrit, while Urdu is written in Nastaliq script, a variant of the Perso-Arabic script, and draws heavily on Persian and Arabic vocabulary. The term "Urdu" also includes dialects of Hindustani other than the standardized languages. Other than these, linguists consider Hindi and Urdu to be the same language.