The quartet of Ga-In, Narsha, Miryo, and JeA helped pioneer the visual and sonic aspects of K-pop that are embraced worldwide today. After debuting in the mid-'00s with primarily R&B ballads, Brown Eyed Girls underwent a transformation and re-emerged with the high-energy electro-pop they are known for. Carried by their breakthrough hit “Abracadabra,” they rose to stardom in Korea, where their Technicolor take on pop set the pace for future groups emerging from the country.