SS501 (pronounced as Double-S 501) is a South Korean boyband under management of Daesung Entertainment, also known as DSP Entertainment. SS501 stands for Superstar and unison of its 5 members until eternity (symbolized by the 0) as 1.

Kim Hyun Joong (Korean: 김현중; Hanja: 金賢重; Japanese: キム･ヒョンジュン)
Birthday: June 6, 1986 (1986-06-06) (age 22)
Position: Leader, Middle-low vocals
Past experience: MC Show Music Core, MC SBS Inki Gayo, MC Mnet Countdown.
Notes: Kim Hyun Joong had been a host of MBC's music show Show! Music Core[2], debuting on November 11, 2006, joining Brian from Fly to the Sky. He left the show in order to make the group's first debut in Japan, at the beginning of 2007. They released 2 albums in Japan, and they are returning to Korea in February, after a concert in China

Heo Young Saeng (Korean: 허영생; Hanja: 許永生; Japanese: ホ･ヨンセン)
Birthday: November 3, 1986 (1986-11-03) (age 21)
Position: High vocals
Past experience: DJ for SBS's "Youngstreet" Radio (from June to August 2006), MC Mnet Countdown.
Notes: Heo Young Saeng was a former trainee under SM Entertainment, he left to join DSP Entertainment. He is close to many TVXQ and Super Junior members, notably Hero Jaejoong, Yesung, and Choi Siwon

Kim Kyu Jong (Korean: 김규종; Hanja: 金圭鐘; Japanese: キム･ギュジョン)
Birthday: February 24, 1987 (1987-02-24) (age 21)
Position: Middle vocals
Past experience: Mnet "Drama - Break", DJ for SBS's "Youngstreet" Radio, MC Mnet Countdown.
Notes: Kim Kyu Jong, along with Park Jung Min, were DJs for SBS's "Youngstreet" radio.

Park Jung Min (Korean: 박정민 Hanja: 朴政珉; Japanese: パク・ジョンミン)
Birthday: April 3, 1987 (1987-04-03) (age 21)
Position: Low vocals
Past experience: MTV Fresh VJ (from March to November 2003), DJ for SBS's "Youngstreet" Radio, MC of a Korean TV Show (MBC): 74434, MC SBS Inki Gayo, MC Mnet Countdown.
Notes: Jung Min is the new MC of a Korean TV Show (MBC) entitled !느낌표: 위대한 유산 74434. This show explores the Korean heritage and its lost treasures. He was also a DJ for "Youngstreet" along with fellow group member Kim Kyu Jong.

Kim Hyung Jun (Korean: 김형준 Hanja: 金亨俊; Japanese: キム・ヒョンジュン)
Birthday: August 3, 1987 (1987-08-03) (age 20)
Position: Middle-high vocals
Past experience: Oak Joo Hyun's (Fin.K.L) Music Video - Catch, MC Mnet Hello Chat (2006), MC Mnet ALBRARY (2008), MC Mnet Countdown.
Notes: Kim Hyung Jun's brother Kim Ki Bum (Marumir/마루미르) was in the new group Xing. His brother has often been confused with Kim Ki Bum of Super Junior.


History
SS501 debuted in 2005 with their first single "경고" ("Warning"), with a second single "Snow Prince" released in late 2005. The group was inactive in Korea for most of 2006, although they had a fan meeting in Japan in April[1]. The hiatus was due to Heo Young Saeng's throat condition which required surgery, thus resulting in a need for time to fully recover.[ citation needed ]. In mid-2006, they held their first concert, "Step Up Concert" in Osaka, Japan. In late 2006, they returned to Korea in order to promote their first full album, which was released on November 10. Singles from the album included "Unlock" and "Four Chance". As well as promoting the album on various variety and music shows, they also filmed a show on MNet called SOS. On their 600th day (January 28, 2007), they won the Mutizen award from SBS Inki Gayo for their song "Four Chance".

Later in 2007, the group debuted in the Japanese market. A Japanese fanclub has been established with the name of "Triple S Japan"; it officially debuted on March 25, 2007, when SS501 will had first official meeting with the group. In Korea, their fan club members number around 417,000[ citation needed ]. The group had a Japanese single "Kokoro", which had multiple versions, including one with all members and five others featuring the members individually. The single debuted at #5 on the Oricon chart.[ citation needed ] A full album was released later in the year.

In 2008, SS501 returned to Korea with their single Deja Vu released on March 8, 2008. The title track was the first song to be promoted, and they started their comeback on music channel M.Net's M Countdown.[1] After success with their single "Deja Vu", they began to promote their second single, "A Song Calling For You". They performed their Goodbye Stage on Music Bank on June 6th, 2008, to return to Japanese activities.

SS501 member Kim Hyun Joong was cast as the F4 member Hanazawa Rui in the Korean version of Hana Yori Dango, which is scheduled to be broadcast via KBS 2TV in the first half of 2009 with a total of 24 episodes. According to an official from Group Eight, the production house in charge of the drama, Kim Hyun Joong was selected to play Rui because he was deemed suited for the character. The decision was based on his performance in the MBC program “We Got Married” where Kim Hyun Joong is being coupled with singer Hwangbo, yet nothing has been officially confirmed due to his busy schedule.


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