For more than 30 years, U2 have quite literally been the flag-wavers for the idea of rock as an agent of social change. Their passion and commitment makes them the ideal choice to represent the letter "U" on our A-Z list of the Best Classic Rock Artists.

Forming at the start of the punk movement, the Irish quartet became one of the biggest acts in rock during the '80s through their politically minded songs. They've since poked fun at their own sense of self-importance, but retained their devotion to environmental causes and fighting poverty and social injustice.

U2 has continued to remain huge, selling out stadiums worldwide with their spectacular and innovative stage presentations.

 

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