BTS (Korean: 방탄소년단; RR: Bangtan Sonyeondan), also known as the Bangtan Boys, is a South Korean boy band formed in 2010 and debuting in 2013 under Big Hit Entertainment. The septet—consisting of members Jin, Suga, J-Hope, RM, Jimin, V, and Jungkook—co-writes and co-produces much of their own material. Originally a hip hop group, their musical style has evolved to incorporate a wide range of genres; their lyrics have often discussed mental health, the troubles of school-age youth and coming of age, loss, the journey towards self-love, and individualism. Their work also frequently references literature, philosophy and psychological concepts, and includes an alternate universe storyline. After launching in 2013 with their single album 2 Cool 4 Skool, BTS respectively released their first Korean-language studio album, Dark & Wild, and Japanese-language studio album, Wake Up, in 2014. The group’s second Korean studio album, Wings (2016), was their first to sell one million copies in South Korea. By 2017, BTS had crossed into the global music market, leading the Korean wave into the United States and breaking several sales records. They became the first Korean ensemble to receive a Gold certification from the Recording Industry Association of America (RIAA) for their single “Mic Drop”, as well as the first act from South Korea to top the Billboard 200 with their studio album Love Yourself: Tear (2018). BTS became one of the few groups since the Beatles in 1966–1968 with four US number-one albums in less than two years, and Love Yourself: Answer (2018) was the first Korean album certified Platinum by the RIAA. In 2020, BTS became the first all-South Korean act to reach number one on the Billboard Hot 100 and Billboard Global 200 with their Grammy-nominated single “Dynamite”. Their follow-up releases “Savage Love”, “Life Goes On”, “Butter”, and “Permission to Dance” made them the quickest act to earn four US number-one singles since Justin Timberlake in 2006.