Exo (엑소) is a South Korean-Chinese boy band produced by S.M. Entertainment. Formed in 2012 in Seoul, South Korea, Exo has of twelve members, which are separated into two subgroups, Exo-K and Exo-M, promoting their music in both South Korea and China. Their name was taken from exoplanet, a term referring to planets outside of the Solar System. Their debut single Mama was released on April 8, 2012, followed by the release of their debut EP Mama on April 9, 2012.