John Michael "Ozzy" Osbourne is an English rock vocalist, songwriter, and television personality. Osbourne rose to prominence in the early 1970s as the lead vocalist of the pioneering band Black Sabbath, whose dark and heavy sound has often been cited as key to the development of the heavy metal genre. Osbourne left Black Sabbath in 1979 and has since had a successful solo career, releasing 11 studio albums, the first seven of which were all awarded multi-platinum certifications in the US, though he has reunited with Black Sabbath on several occasions, most recently in 2011 to record the album 13, which was released in 2013. Osbourne's longevity and success have earned him the informal title of "Godfather of Heavy Metal". Osbourne's total album sales from his years in Black Sabbath combined with his solo work is over 100 million. As a member of Black Sabbath he was inducted into the US Rock and Roll Hall of Fame, and was inducted into the UK Music Hall of Fame as both a solo artist and as a member of the band. He has a star on the Birmingham Walk of Stars in his hometown, and also has a star on the Hollywood Walk of Fame. In the early 2000s, he became a TV star, appearing as himself in the MTV reality program The Osbournes, alongside wife/manager Sharon and two of their three children, Kelly and Jack.