The song is originally made by Shel Silverstein, from his 1962 album Inside Folk Songs.
The song is literally “gallows humor”, as it is sung by a man awaiting his own execution by hanging. Each verse consists of two lines, of which the first line is anything from humorous to poignant, and the second line is a minute-by-minute countdown.
Cash’s cover, as usual the most known one, appears on both Sings the Ballads of the True West and on his 1968 live album, At Folsom Prison.