"I Walk The Line" Album Sales Milestone [Getty Images]

MEMPHIS, TN - MAY 1: Sun Records founder Sam Phillips poses for a portrait with country singer/songwriter Johnny Cash as he gives him a framed record of the song "I Walk The Line" to commemorate a milestone in album sales which was released on May 1, 1956 in Memphis, Tennessee. (Photo by Colin Escott/Michael Ochs Archives/Getty Images)

Michael Ochs Archives Colin Escott