Hindi refers to an Indo-European language spoken mainly in northern and central India, is the primary official language of the Union government of India. It is part of a dialect continuum of the Indic family, bounded on the northwest and west by Punjabi, Sindhi, Urdu , and Gujarati; on the south by Marathi ; on the southeast by Oriya; on the east by Bengali; and on the north by Nepali. Hindi is the National Language of India and the regional language of six states- Haryana , Rajasthan, Uttar Pradesh, Bihar, Madhya Pradesh and Himachal Pradesh. It is spoken by 437 million people in the world. Hindi is the official language of India.