U2 is a rock band.
Achtung Baby ( [ pronˈɑːktuːŋ_ˈbeɪbiː ] ) is the seventh studio album by Irish rock band U2 . Songs of Innocence is the thirteenth studio album by Irish rock band U2 . U2 . Beginning with their acclaimed seventh album , Achtung Baby ( 1991 ) , and the multimedia intensive Zoo TV Tour , the band integrated influences from alternative rock , electronic dance music , and industrial music into their sound , and embraced a more ironic , flippant image .