(Infos from official web wiki)
SJ-K.R.Y, established in November 2006, is a trio formed by Kyuhyun, Ryeowook, and Yesung (in personal opinion, the best singers in suju:P) whose initial K.R.Y makes up the name of the group.
They are credited to singing mournful and R&B-style ballads.
“한 사람만을” is the my favorite song of them> <
SJ-T contains six suju members, Leeteuk (the leader), Heechul, Kangin, Shindong, Sungmin, and Eunhyuk.
The group is known for capitalizing trot music, the oldest form of Korean pop music.
SJ-Happy consists of every previous member from SJ-T except Heechul, who is replaced by Yesung.
Their music style involves the common style of contemporary dance music and bubblegum pop, mainly targeting the music industry with refreshing rhythm and quirky lyrics. Their goal is to give fans feelings of bliss and happiness with their music.