How U2 changed their sound

U2 evolved their sound and are possibly one of the most successful bands of the 1980s. The band evolved from post-punk on 1980's Boy to a more straightforward rock sound by 1983's War then they looked into blues and country for 1987's The Joshua Tree and 1988's Rattle and Hum. With 1991's Achtung Baby, they had a complete genre shift to a more modern alternative rock sound and added more electronics, eventually culminating in the ambient concept album 1995's Original Soundtracks 1 (released under the pseudonym Passengers) and the largely electronic 1997's Pop. After that, they went back to a more Joshua Tree style sound with 2000's All That You Can't Leave Behind. 2009's No Line on the Horizon manages to combine just about everything from the rest of their career, with Joshua Tree anthems and Achtung Baby rockers right next to Passengers-style ambient pieces on the track listing.