Hindu refers to an identity associated with the philosophical, religious and cultural systems that are indigenous to the Indian subcontinent. As used in the Constitution of India, the word “Hindu” is attributed to all persons professing any Indian religion. In common use today, it refers to an adherent of Hinduism. With more than a billion adherents, Hinduism is the world’s third largest religion. The vast majority of Hindus, approximately 940 million, live in India.