One Day (South Korean band)
South Korean boy band
One Day (Korean: 원데이) was an eleven-member South Korean band formed by Korean musician Park Jin-young of JYP Entertainment. After performing as one group, it was splintered into two separate bands, the ballad-oriented group 2AM and the dance-focused group 2PM. Since their debut, 2AM and 2PM members have frequently appeared together on YouTube videos and television programs, collaborated on songs, and performed together.
Formation
A reality TV series on Mnet called Hot Blood Men captured the group's rigorous training program and had viewers vote on which trainees would debut. Former member Jay Park (Jaebeom) received the most fan votes, finishing in the top spot, while three trainees were eliminated: Lee Swichi, Jeong Jin-woon, and Yoon Doo-joon who were all cut. However, Jinwoon replaced Im Daehun upon the latter's withdrawal. By the end of the training process, One Day had been reduced to an eleven-member group.
Split
The band was then split into four-member ballad group 2AM and seven-member hip-hop group 2PM.
2AM (Korean: 투에이엠; RR: Tueiem), became a four-member boy band and ballad group consisting of:
Jo Kwon
Lee Chang-min
Lim Seul-ong
Jeong Jin-woon
2PM (Korean: 투피엠; RR: Tupiem), became a seven-member hip hop band formed by JYP Entertainment, consisting of:
Jun. K (formerly known as Kim Junsu)
Nichkhun Buck Horvejkul
Ok Taec-yeon
Jang Wooyoung
Lee Jun-ho
Hwang Chan-sung
Jay Park (also known as Park Jaebeom; left 2PM in September 2009).
Collaborative work
As labelmates, 2AM and 2PM members have frequently appeared together on YouTube videos and variety TV programs such as Win Win, Star King, Star Golden Bell, and Strong Heart, collaborated together on songs, and performed together at JYP Nation concerts.
In 2009, as part of a project for 2PM's variety show Wild Bunny, 2AM members Jo Kwon and Lim Seul-ong joined Ok Taec-yeon, Jang Wooyoung, and Hwang Chan-sung in filming a parody music video of Brown Eyed Girls' song "Abracadabra" under the group name of Dirty Eyed Girls.
Begin with the source’s own compact description: “One Day (South Korean band)” is south Korean boy band. The dossier treats that line as a proposition to test through South, Korean and band, not as a finished interpretation.
Why this record matters
The phrase “south Korean boy band” supplies a clear boundary for inquiry. It also exposes the unanswered questions: who defined that boundary, when it became stable and which sources sit outside it.
The citation trail is more important than the brevity of the summary: it shows where individual claims can be examined in context. The source revision retrieved here is dated Sep 27, 2026. The linked authority identifier is Q48999786. None of the 0 selected statements returned an explicit reference. The first chronological checks are 2009.
The absence of detail may reflect summary conventions rather than a lack of surviving documentation. The source lead contains qualifying language; that uncertainty should survive quotation, summary and reuse. Authority statements aid reconciliation but still require their own references, qualifiers and ranks to be checked.
How to read it
Use the entry as an orientation point, then follow its citations and revision history. Names, dates and institutional relationships should be checked against the original record.
- Subject orientation
- Search vocabulary
- Locating named sources
The closest primary source, responsible institution and strongest cited specialist reference.
Three-step research path
- Establish the record: confirm the title “One Day (South Korean band)”, its source revision and the description used here.
- Expand the search: follow One Day (South Korean band) primary sources, One Day (South Korean band) archive and South research across catalogues and specialist indexes.
- Test the account: compare the strongest cited source with the responsible institution’s current record and note any disagreement.
Questions for further research
- Which source most directly establishes the central claim about “One Day (South Korean band)”?
- What terminology or title could unlock a more precise catalogue search?
- Which cited source is closest to the event, object or claim?
Search terms from this dossier
This entry incorporates text from “One Day (South Korean band)” on English Wikipedia. Contributors are listed in the page history. Text is available under the Creative Commons Attribution-ShareAlike 4.0 License. Selected authority identifiers and statements are retrieved from Wikidata under CC0; their references and qualifiers remain part of the verification path.