Kidz Bop is a brand of compilation albums featuring child session musicians performing contemporary music. The company was founded by Cliff Chenfeld and Craig Balsam in 2001 under Razor & Tie Entertainment. The albums are composed of "kid-friendly" versions of the latest songs on Top 40 radio and are sung by young children. Each year, Kidz Bop releases 2 volume CDs, as well of 4 "music compilations". According to Billboard, three Kidz Bop albums were among the top ten children's albums sold in 2010, including both of the top two albums.