Short answers, pulled from the story.
Hollywood Undead originated on the 3rd of June 2005, when Jorel Decker, Aron Erlichman, and Jeff Phillips posted a song called "Hollywood" to the band's MySpace profile. The positive response led them to form the full group with George Ragan, Jordon Terrell, Dylan Alvarez, and Matthew Busek.
Hollywood Undead's debut album was Swan Songs, released on the 2nd of September 2008. It entered the Billboard 200 at number 22 in its first week, selling 21,000 copies.
Deuce, born Aron Erlichman, left Hollywood Undead in early 2010 due to creative differences. Band members cited arguments over writing credits, his reluctance to tour, and a dispute over bringing a personal assistant on the road as the reasons for his departure.
Daniel Murillo, the lead singer of Lorene Drive, replaced Deuce. Murillo had recently advanced past the auditions for season 9 of American Idol but chose to leave the competition and join Hollywood Undead instead.
Notes from the Underground, released on the 13th of January 2013, is the band's highest-charting album. It sold over 53,000 copies in its first week, reached number 2 on the Billboard 200, and hit number 1 on Canada's Top Albums chart.
Johnny 3 Tears described the band in a 2020 interview as an industrial hip-hop group, calling their sound "an amalgamation of Nine Inch Nails and the Beastie Boys." Critics have also classified them under rap rock, nu metal, and labels like "myspace-core" and "scene-core".