John Lennon was a member of one of the world's most successful group ever: The Beatles. But he will always be remembered as someone who educated us all to the idea of world peace.
Together with his wife Yoko Ono, he attempted to transform the world through non-musical means until he was assassinated on December 8, 1980 by a gunman outside his apartment building in Manhattan.
"Give Peace A Chance" or "Happy Christmas (War Is Over)", with an embarrassingly simple message: "War is over if you want it" are two of his most famous songs.
But it is "Imagine" his greatest legacy. An extraordinarily simple song, with a combination of that simplicity and the timeless lyrics that make it one of the finest songs of the century.