The K-pop girl group 4Minute formed in Seoul, South Korea, in May 2009. The group's blend of R&B, hip-hop, and electronic dance music helped differentiate 4Minute's sound from that of other K-pop acts, resulting in an award-winning career and several Number 1 releases. Comprised of vocalists Nam Ji-hyun, Heo Ga-yoon, Jeon Ji-yoon, Kwon So-hyun, and former Wondergirls member Kim Hyun-a, 4Minute debuted with the single "Hot Issue" in June 2009 and released the debut EP For Muzik that August. For Muzik peaked at Number 2 on the South Korean charts, followed by the similarly-successful EP Hit Your Heart in May 2010. Diamond, the group's first full-length release, was released later that year, climbing to Number 10 in South Korean and Number 27 in Japan. A second album, 4Minutes Left, followed in 2011, featuring the Top 5 hits "Heart to Heart" and "Mirror Mirror." From 2012 until the band's dissolution in 2016, 4Minute released an EP every year, topping the Gaon Album Chart with 2012's Volume Up and climbing to Number 2 with the subsequent records Name Is 4Minute, 4Minute World, Crazy, and Act. 7. Along the way, the group scored Number 1 hits with "What’s Your Name?" and "Whatcha Doin' Today." The group disbanded during the summer of 2016, with all five members pursuing separate careers in film, television, and music during the following years.