What is "ozzfest"

Ozzfest is an annual festival tour of the United States and sometimes Europe (and for the first time Japan in 2013) featuring performances by many heavy metal and hard rock musical groups. It was founded by Ozzy Osbourne and his wife Sharon Osbourne, both of whom also organise each yearly tour with their son Jack Osbourne. The Ozzfest tour has featured bands of a variety of genres within heavy metal and hard rock, including alternative metal, thrash metal, industrial metal, metalcore, hardcore punk, deathcore, nu metal, death metal, post-hardcore, gothic metal and black metal. Ozzy Osbourne and Black Sabbath have played the tour several times over the years.