Winner (Korean: 위너; romanized: wineo; stylized in all caps) is a South Korean boy band consisting of four members: Jinu, Hoony, Mino, and Seungyoon. The band was formed in 2013 by YG Entertainment through Mnet's survival program WIN: Who Is Next leading to their official debut on August 17, 2014, with studio album 2014 S/S. Originally a five-piece band, Taehyun departed in November 2016 for his mental health and well-being. Upon their debut, The Korea Herald cited their immediate success as "unprecedented" for a new group, thus dubbed as "Monster rookies". Winner is often cited as a "self-producing" band with all members actively taking on roles from producing and choreographing to designing and marketing. The band also earned the titles "Trust and Listen" alongside "Kings of Summer" by media outlets and the general public through releases.

As of March 2019, Winner was recorded as the fastest Korean act to top the Billboard World Album Chart with their debut album 2014 S/S, and topped domestic charts on Gaon for both their album and lead single "Empty". Winner is currently the fastest act to win on a televised music show, with a time of five days. As of October 2019, they are the only artists to have all lead singles consecutively top Melon five years straight since debut. Their success in Asia earned them numerous awards for music, fashion and popularity including the Melon Music Awards, MTV Asia Music Gala and Style Icon Awards. Following the band's reformation, Winner's lead single, "Really Really" from their first single album Fate Number For (2017), instantly went to number one in South Korea. It went on to sell over 2.5 million digital copies domestically and surpass 100 million streams on Gaon, making Winner the first-ever K-pop boy group in history to achieve this while keeping their "Chart-In" status.

Throughout their career, the band cumulatively held over 100 concerts. Their first world tour, Winner Everywhere Tour in 2018, was the band's largest tour to date. Winner is also known through endorsement deals with brands Adidas, Oreo, Kiehl's and more. The band actively participates in various charitable activities and animal campaigns.