"Happiness" (Korean: 행복; RR: Haengbok) is the debut single recorded by South Korean girl group Red Velvet. The song was written by Yoo Young-jin, Will Simms, Chad Hugo, Anne Judith Wik, and Chris Holsten, with the production was handled by Hugo and Simms. It was released digitally by SM Entertainment on August 4, 2014, in South Korea. The song also marked their first release under the Red Velvet moniker and their first as a quartet, introducing the four members Irene, Seulgi, Wendy, and Joy to the public. An urban Euro-pop track, it is about how you can feel empowered and love yourself more by appreciating the small joys in life. Upon its release, "Happiness" received mixed reviews from music critics for its mish-mash of different sounds and styles and not much satisfaction with just this one song. The song charted moderately in South Korea, becoming the group's first top five entry on both the Gaon Digital Chart and Billboard's World Digital Songs chart. An accompanying music video was released on August 3, 2014, but a new version was reuploaded due to references to the Atomic bombings of Hiroshima and Nagasaki and the September 11 attacks. Red Velvet's debut stage for the song was a performance on Music Bank and further promotion was held on several South Korean music programs.