India has more than 50% of its population below the age of 25 and more than 65% below the age of 35. It is expected that, in 2020, the average age of an Indian will be 29 years, compared to 37 for China and 48 for Japan; and, by 2030, India's dependency ratio should be just over 0.4.
Further complexity is lent by the great variation that occurs across this population on social parameters such as income and education. Only the continent of Africa exceeds the linguistic, genetic and cultural diversity of the nation of India.
The Languages of India belong to several language families, the major ones being the Indo-Aryan languages (a subbranch of Indo-European) spoken by 74% of Indians and the Dravidian languages spoken by 23% of Indians.
Other languages spoken in India belong to the Austroasiatic, Tibeto-Burman, and a few minor language families and isolates.
The official language of the Central Government of Republic of India is Standard Hindi, while English is the secondary official language.
The constitution of India states that "The official language of the Union shall be Hindi in Devanagari script." a position supported by a High Court ruling.
However, languages listed in the Eighth Schedule of the Indian constitution are sometimes referred to, without legal standing, as the national languages of India.
Individual mother tongues in India number several hundred; the 1961 census recognized 1,652 (SIL Ethnologue lists 415).
According to Census of India of 2001, 30 languages are spoken by more than a million native speakers, 122 by more than 10,000.
Three millennia of language contact has led to significant mutual influence among the four language families in India and South Asia. Two contact languages have played an important role in the history of India: Persian and English.