f(x) debuted in 2009 under the SM Entertainment label. That same year, After School, 2NE1, and BEAST (B2ST) also were introduced to Kpop fans. f(x) has five members: Song Qian (Victoria), Amber Josephine Liu (Amber), Park Sun Young (Luna), Choi Jin Ri (Sulli) and Jung Soo Jung (Krystal). The group is known for its international membership -- Victoria is from China, while Amber and Krystal hail from the United States. Each member has their own distinct personality or skill: Victoria often showcases her athletic abilities, while Amber has a distinct androgynous look and powerful rapping skills. Luna has a strong singing voice, and Krystal and Sulli are known for their beauty and youthful spirit, respectively. These personalities and skills create infinite combinations when combined, giving credence to their name, the algebraic function, f(x).
f(x) is an active group that produces urban pop and electronica music with touches of rhythm and blues. They have won several music and cultural awards since their debut. In addition to releasing their second Korean- language mini album, f(x) will debut in Japan in 2012.