소녀시대 (So Nyeo Si Dae), known worldwide as Girls' Generation or 少女時代 in japan, is an eight member girl group from Seoul, South Korea formed in 2007 by SM Entertainment. The group debuted on SBS Inkigayo on August 5, 2007, performing their first single, "다시 만난 세계 (Into the new world)". Girls' Generation is considered South Korea's No. 1 girl group.
The members are (in order of official announcement): 윤아 (Yoona), 티파니 (Tiffany)