U2 is a successful, four-member Irish rock band formed in Dublin in the late 1970s.
Mention of this band generally polarizes opinion, with die hard fans referring to them as the greatest band in the world and non-fans referring to them as the worst, most pompous, least talented or most annoying band in the world. (U2's political activism produces the same disparity of opinion.)
NOTE: The second paragraph of this definition can be applied to most rock bands and various other celebrities, because it is apparently not enough for the human animal to say, "No, I don't care for ____" (fill in the blank) and leave it at that; the dislike must seemingly be expressed in hearty invective and insults as creative and inflammatory as the writer can produce. This behavior can be noted in most entries at Urban Dictionary which concern rock bands.
Fan: I love U2 (or other band that fan is enamored of), they are the greatest band in the world!
Non-fan: I hate them, they suck, they're awful and talentless and ugly and stupid and annoying and... (and so forth.)