Ronnie James Dio was an Italian American heavy metal vocalist and songwriter. He fronted numerous groups including Elf, Rainbow, Black Sabbath, Heaven & Hell, and his own band, Dio. He is credited with popularizing the "metal horns" hand gesture in metal culture and is known for his medieval themed lyrics. Dio possessed a powerful versatile vocal range capable of singing both hard rock and lighter ballads and according to Rainbow/Deep Purple guitarist Ritchie Blackmore upon hearing him sing, "I felt shivers down my spine." Dio sold over 47 million albums throughout his career.