Languages with official status in India
The Constitution of India designates the official language of the Government of India as Hindi written in the Devanagari script, as well as English. There is no national language as declared by the Constitution of India. Hindi is used for official purposes such as parliamentary proceedings, judiciary, communications between the Central Government and a State Government. States within India have the liberty and powers to specify their own official language(s) through legislation and therefore there are 22 officially recognized languages in India of which Hindi is the most used. The number of native Hindi speakers is about 25% of the total Indian population; however, including dialects of Hindi termed as Hindi languages, the total is around 44% of Indians, mostly accounted from the states falling under the Hindi belt. Other Indian languages are each spoken by around 10% or less of the population.
Hindi Belt
The Hindi Belt or Hindi Desh, sometimes referred to as the Hindi-Urdu Region, is a linguistic region in north-central India where Hindi (and the various languages/dialects grouped under it) and Urdu are widely spoken. Hindi belt is sometimes also used to refer to nine Indian states whose official language is Hindi and have a Hindi-speaking majority, namely Bihar, Chhattisgarh, Haryana, Himachal Pradesh, Jharkhand, Madhya Pradesh, Rajasthan, Uttarakhand , Uttar Pradesh and National Capital Territory of Delhi.