Hindi is the most widely spoken language of India, and is the primary official language of the Republic of India.
According to the number of native speakers, Hindi is the fourth most widely spoken language in the world, after English (third), Spanish (second), and Mandarin Chinese (first). Such rankings are approximate, of course, depending on whether non-native speakers of Hindi and Hindi dialects are included.
It is difficult to estimate how many Indians speak Hindi as their native or secondary language. However, it is important to note that India is a very diverse country in which many languages are spoken, and thus not all Indians speak Hindi. According to the 2001 census, 43% of Indians speak Hindi as their native language, and an additional 27% – 43% speak the language as a second language or at least understand the language.
Hindi is spoken widely in the north-central regions of India. It is spoken much less widely in South India. India is spoken as the primary language in the states of Madhya Pradesh and Uttar Pradesh.
Hindi is additionally spoken in many other countries throughout the world. A large number of Indian expatriates live in English-speaking regions such as the United Kingdom, America, Australia, New Zealand, Canada, and South Africa. Hindi is spoken in countries which neighbor India, such as Bangladesh and Nepal. Hindi and Urdu are essentially the same language, and Urdu is spoken in Pakistan.
Hindi derives its vocabulary from several major sources, including Sanskrit, Persian, and Arabic. English vocabulary has been incorporated into Hindi also, especially in colloquial Hindi.
Hindi and Urdu are essentially different registers of the same language. They differ mainly in vocabulary, most prominently in formal and literary styles. Literary Hindi draws from Sanskrit whereas literary Urdu draws from Persian and Arabic. However, in colloquial Hindi-Urdu, the vocabulary is mixed. Grammatically, the two languages are basically identical.