T.O.P (Korean: 탑; born Choi Seung Hyun, 최승현 on November 4, 1987) is one of five members of the South Korean Hip Hop group Big Bang from YG Entertainment.

The "Big Brother" of the band is Choi Seung Hyun (최승현), also known as Tempo or T.O.P. YG's staff calls him Keun Seung Hyun, meaning Big Seung Hyun, to distinguish between the two Big Bang members named Seung Hyun, the other being Seung Ri born Lee Seung Hyun. Before joining Big Bang, he performed in clubs and even won KBS Radio's "Rap Battle" in 2003. Tempo is one of the two rappers in the Big Bang and is also very talented in beat-boxing. TOP has successfully finished filming his role as the school's top fighter in a Korean drama called, I Am Sam. His character's name in the drama was Chae Mu Shin and his talent as an actor has impressed the fans and the viewers as well. He has been featured in videos of various artist like Red Roc's Hello, Gummy's I'm Sorry and Uhm Jung Hwa's D.I.S.C.O.