f(x)

f(x) was a five-member girl group under SM Entertainment. On September 5, 2009, they made their official debut with the digital single "La Cha Ta".

Their debut studio album, Pinocchio (2011) and two extended plays NU ABO and Electric Shock produced three number-one singles on South Korea's Gaon Digital Chart. Their widely acclaimed second studio album, Pink Tape (2013), was the only K-pop album on the "41 Best Albums of 2013" list on the US music channel Fuse, the only idol album to be included on the "Top 100 Classic Albums of All Time" list compiled by Korean critics, and it was named "Greatest K-pop Album of the 2010s" by Billboard. The group has presumably disbanded with the departures of three members in 2019. f(x) has never formally broken up, although many people refer to f(x) in the past tense.