U2
U2 are an Irish Rock band, consisting Bono (vocals), The Edge (Lead Guitar), Adam Clayton (Bass) and Larry Mullen Jr. (Drums). Their most famous albums are The Joshua Tree and Achtung Baby, and they gained recognition as a Stadium Rock band with the Zoo TV Tour.
U2 were supposedly an influence on Absolution and Black Holes and Revelations. The Edge was also supposedly an influence as a guitarist on Matt Bellamy. Muse were also the supporting act for U2's 360 Tour in North America, which took place before the actual "The Resistance Tour" started. The band thought this would be a great opportunity to get warmed up for their own tour, as well as learn from U2.
The Edge joined Muse on stage at Glastonbury 2010 to perform "Where the Streets Have no Name". U2 were due to play this at Glastonbury themselves, before Bono's back injury caused them to cancel.