Hindi, or more precisely Modern Standard Hindi, is a standardised and sanskritised register of the Hindustani language . It is the native language of people living in Delhi, Haryana, Western Uttar Pradesh, Bihar, northeastern Madhya Pradesh, and parts of eastern Rajasthan, and is one of the official languages of the Republic of India. But many non-native speakers from other parts of India, too, understand it easily because it is close to their native languages that, just like Hindi, originated from various Prakrit languages. These languages have common roots and the native speakers of several regional Indian languages find it easier to understand the more Sanskritised form of Hindi. Wikipedia