Hindustani language
Hindi

Hindi is declared by Article 343(1), Part 17 of the Indian Constitution as the "official language (राजभाषा, rājabhāṣā) of the Union." (In this context, "Union" means the Federal Government and not the entire country —India has 23 official languages.) At the same time, however, the definitive text of federal laws is officially the English text and proceedings in the higher appellate courts must be conducted in English.

At the state level, Hindi is one of the official languages in 10 of the 29 Indian states and three Union Territories, respectively: Bihar, Chhattisgarh, Haryana, Himachal Pradesh, Jharkhand, Madhya Pradesh, Rajasthan, Uttarakhand, Uttar Pradesh and West Bengal; Andaman and Nicobar Islands, Dadra and Nagar Haveli, and Delhi.

In the remaining states, Hindi is not an official language. In states like Tamil Nadu and Karnataka, studying Hindi is not compulsory in the state curriculum. However, an option to take the same as second or third language does exist. In many other states, studying Hindi is usually compulsory in the school curriculum as a third language (the first two languages being the state's official language and English), though the intensiveness of Hindi in the curriculum varies.
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