"U mad" or "you mad" is an internet catchphrase commonly associated with trolling. The phrase is used both as a statement and a question. It was popularized after an incident on The O'Reilly Factor involving rapper Cam'ron and record producer Damon Dash in 2003. Host Bill O'Reilly was debating the effect of rap music on children. When O'Reilly began to interrupt Dash, Cam'ron stated, "Why don’t you want to let him talk? You mad. You mad." In 2004, the phrase was added to Urban Dictionary, citing Cam'ron as the coiner.
The phrase caused controversy in 2011 when students at Kirtland High School in Ohio displayed a banner reading "YOU MAD BRO" at a football game against a rival school. The president of the local NAACP chapter, who was present at the game, accused the students of racial intimidation.
"U Mad" is also the name of a 2015 single by Vic Mensa featuring Kanye West.