The song's origin and basis are unclear, with some thinking that the song commented on the assassination of John F. Kennedy, as the song was recorded three months after the assassination, although Simon & Garfunkel had performed the song live as Kane & Garr two months before the assassination.

The final verse was written about Simon's then-wife Peggy Harper, who had noticed her first gray hairs ("Sail on, silvergirl"). It does not refer to a drug abuser's hypodermic needle, as is sometimes claimed. The verse was Garfunkel's idea, but Simon reportedly did not like it.

Ever wonder what Paul Simon thought of Disturbed's 2015 rendition of Simon & Garfunkel's "The Sound of Silence"? During a recent interview on The Howard Stern Show, the iconic singer/songwriter/guitarist shared his thoughts on the cover. "I liked it very much… It was accomplished very well".

"We were really best friends up until Bridge over Troubled Water,” Simon says about his former bandmate and friend since elementary school Art Garfunkel, 82. “[Afterwards], it didn't have the harmony of the friendship… that was broken.”