Anthony Frank "Tony" Iommi (/aɪˈoʊmiː/; born 19 February 1948) is an English guitarist, songwriter and producer. Best known as lead guitarist and founding member of the pioneering heavy metal band Black Sabbath, he has been the band's sole continual member and primary composer. Iommi is widely considered one of the most influential rock guitarists of all time. A prolific riff writer, he was ranked number 25 in Rolling Stone magazine's list of the "100 Greatest Guitarists of All Time".