U2 () are a rock band from Dublin, Ireland. The band consists of Bono (vocals and guitar), The Edge (guitar, keyboards and vocals), Adam Clayton (bass guitar) and Larry Mullen, Jr. (drums and percussion).

U2 formed in 1976 when the members were teenagers with limited musical proficiency. By the mid-1980s, however, the band had become a top international act, noted for their anthemic sound, Bono's impassioned vocals, and The Edge's textural guitar playing. Their success as a live act was greater than their success at selling records until their 1987 album The Joshua Tree increased the band's stature "from heroes to superstars," according to Rolling Stone. U2 responded to the dance and alternative rock revolutions, and their own sense of musical stagnation by reinventing themselves with their 1991 album Achtung Baby and the accompanying Zoo TV Tour. Similar experimentation continued for the rest of the 1990s. Since 2000, U2 have pursued a more traditional sound that retains the influence of their musical explorations.

U2 have sold more than 170 million albums worldwideVallely, Paul. "Bono: The Missionary". The Independent, May 2006. Retrieved 15 October 2006. and have won more Grammy Awards than any other band.Grammy Winners List grammy.com. Retrieved 15 October 2006.

In 2005, the band were inducted into the Rock and Roll Hall of Fame in their first year of eligibility. Rolling Stone Magazine listed U2 at #22 in their list of the 100 greatest artists of all time.The Immortals: The First Fifty. Rollingstone.com (24 March 2004). Retrieved on 2008-02-08. Throughout their career, as a band and as individuals, they have campaigned for human rights and social justice causes, including Amnesty International, the ONE Campaign, and Bono's DATA (Debt, AIDS, Trade in Africa) campaign.