Do you have a favorite song? One single, absolute specimen that perfectly encapsulates everything that you love about music, to the point where it defines your entire musical experience? Most people have songs that they will always love, as well as albums, bands and genres, but I don't think that many can say without a doubt that they hold one song above all others.
For me, "Paint It Black," a 1966 single by the Rolling Stones is the greatest song ever recorded. The pounding drums, the sitar, the incredibly dark lyrics, these all come together to make an absolutely perfect single. Nothing else will ever come close to the definitive masterpiece that the Stones captured in those three-and-a-half minutes.
Decca records actually lists the song with as "Paint It, Black," with a superfluous comma breaking up the title. I choose to ignore it.