what is "hung up"?
It is a song by American singer Madonna
Hung Up
"Hung Up" is a song by American singer Madonna 
madonna every little thing that you say or do UNANSWERABLE
wiki:6935757
Hung Up [SEP] Introduction
"Hung Up" is a song by American singer Madonna from her tenth studio album "Confessions on a Dance Floor" (2005). Initially used in a number of television advertisements and serials, the song was released as the album's lead single on October 17, 2005. Written and produced by Madonna in collaboration with Stuart Price, "Hung Up" prominently features a sample from the instrumental introduction to ABBA's single "Gimme! Gimme! Gimme! (A Man After Midnight)", for which Madonna personally sought permission from its songwriters, Benny Andersson and Björn Ulvaeus. This is thought to be only the second time Andersson and Ulvaeus have given permission to sample one of their songs, following Fugees song "Rumble in the Jungle" for the soundtrack of the film When We Were Kings.