Many mistakenly believe that Jack o' Lantern was a damned soul, doomed to wander listlessly forever, or that pumpkins carved into Jack o' Lanterns are supposed to hold souls. While the former is partially true, it casts a negative shadow on the true story of Jack o' Lantern, which goes something like this, with variation:
There once was a farmer named Jack, who was both very lazy and very quick witted. Now one day, the Devil came to Jack to tempt him, but Jack tricked the Devil into climbing a tree. The Devil could not climb down, and asked Jack for help.
On one condition, Jack replied. That you not allow me into hell.
The Devil could not very well refuse, so he grudgingly agreed and Jack helped him down.
As everything does, eventually Jack died.
He went straight to hell, but the Devil kept his word, and would not let him in.
Jack traveled to heaven, but he had been so bad during his life, they would not let him in heaven either.
So Jack hollowed out one of his gourds, it was originally a turnip, and made a lantern out of it.
Even now he wanders the face of the world, trying to find somewhere he can stay.
Jack is generally described as very tall and lanky, but not unlikable.
He is also personified in a couple of works, among which: The Halloween Tree by Ray Bradbury
As Carapace Clavicle Moundshroud
And in Tim Burton's film The Nightmare Before Christmas
As Jack Skellington.
Jack o' Lantern is analogous to Jack o' the Shadows & Death Itself.