Procol Harum (/ˈproʊkəl ˈhɑːrəm/) is an English rock band formed in 1967. Their best-known recording is the 1967 hit single "A Whiter Shade of Pale", one of the few singles to have sold over 10 million copies. Although noted for their baroque and classical influence, Procol Harum's music is described as psychedelic rock and proto-prog. In 2018, the band was honoured by the Rock and Roll Hall of Fame when "A Whiter Shade of Pale" was inducted into the brand-new Singles category.