The D chord, famed for its part in innumerable classic rock songs, including 'Back in Black,' 'Bad Moon Rising,' and 'Don't Be Cruel,' was retired Tuesday during a ceremony at the Rock and Roll Hall of Fame and Museum. 'The D chord has firmly cemented its place in rock history,' said Hall of Fame founder and Rolling Stone publisher Jann Wenner at the induction, during which Eric Clapton, Chuck Berry, Pete Townshend, R.E.M.'s Peter Buck, and several other rock luminaries simultaneously performed the chord one last time. 'We are proud to honor the legacy of this immortal and eminently prestigious musical tone by never allowing it to be played again in any genre of rock music.' The D chord will take its place in the museum's permanent collection alongside Jimi Hendrix's guitar, David Bowie's Ziggy Stardustera platform boots, and the whole-note rest. 