Seo Joo-hyun, commonly known by her stage name Seohyun, is a South Korean singer, sixth and youngest member of the hit Korean Girl group, Girls' Generation.Seohyun was born on June 28, 1991, in Seoul, South Korea as an only child. She attended Seoul Middle School and Daeyoung High School, from which she graduated on February 9, 2010 with the Achievement Award and currently attends Dongguk University, majoring in acting like her fellow member, Yoona. She stays in an apartment with Girls' Generation. She is roommates with fellow member Hyoyeon. --wikipedia
Seohyun was a trainee of SM Entertainment for six years and six months and was discovered in the 2001 SM Casting System. She had her solo song number with "I Dont Know Love" on the KBS Gayo Festival in December 31, 2007. Seohyun released various singles with Jessica and Tiffany — the first called "Oppa Nappa" and the second titled "Mabinogi (It's Fantastic!)", a theme song for a video game. On February 17, 2009, Seohyun sang a duet with trot Joo Hyun-mi (feat. Davichi called "JjaRaJaJja". The song earned an nomination from the 2009 M.net Asian Music Awards for Trot Music of the Year. She also sang the song "S.E.O.U.L." with Super Junior's Kyuhyun, Ryeowook, Sungmin and Donghae and fellow Girls' Generation members Taeyeon, Jessica, Sooyoung and Sunny. In addition to her appearances on various shows with Girls' Generation, she is part of MBC's reality-variety show We Got Married partnered with singer Jung Yong Hwa, who is the leader of K-pop band CN Blue.