Rai Sahib / Rao Sahib / Roy Sahib, abbreviated R.S., was a title of honour issued during the era of British rule in India to individuals who performed great service in visionary leadership to the nation. The title was accompanied by a medal. Translated, sahib means "leader".
This was the start level title usually awarded to civilians, which could later be upgraded to Rao Bahadur and then to Dewan Bahadur titles.
The title styled Rai Sahib were awarded to Hindu people of North India, Rao Saheb in Maharashtra and styled Rao Sahib to Hindu people of South India, however, they were both of same category and spelling was altered to meet with regional differences of pronunciation. Whereas, another spelling variation Roy Sahib was awarded to Hindu people of Bengal region of British India.
The Rai Sabib/Rao Sahib/Roy Sahib and other similar titles issued during British Raj were disestablished in 1947 upon independence of India.