Since debuting in 2007, Wonder Girls have become one of K-pop's top girl groups, beloved for their attitude-heavy retro-pop jams—and eventually respected for their musicianship too. Their breakthrough came in 2008 with the one-two punch of the snappy “So Hot (3rd Project)”—with its iconic “omona” hook—and the Motown homage “Nobody”, setting the tone for their fun and funky later singles. As the group matured, they became a full-fledged instrument-wielding band. But they stayed true to their throwback style, firing up keytars for the '80s-inspired “I Feel You”.