Traditions have always played a big part in what defines any holiday. Christmas brings unique traditions like putting up a tree and singing carols for strangers. But Halloween may be richer in tradition than any other holiday. Children dress up in costumes and go house to house, asking for candy handouts with the familiar cry of "trick or treat." There's another Halloween tradition from Ireland that you can spot on porches all over the United States and parts of Europe on 31 October; the jack-o'-lantern.
Stingy Jack O’Lantern, also known as Jack the Smith, Drunk Jack, Flaky Jack or Jack-o’-lantern, is a mythical character associated with All Hallows Eve or nowadays called Halloween, while also acting as the mascot of the holiday. The "jack-o’-lantern" may be derived from the character.
Like most folklore, the history of the jack-o'-lantern varies a little bit depending on who's telling the story. But all stories involve a clever drunkard that pulls one over on the devil.
As the story goes, several centuries ago in Ireland, there lived a drunkard known as Stingy Jack. He was known throughout the land as a deceiver or manipulator. On a fateful night, Satan overheard the tale of Jack's evil deeds and silver tongue. Unconvinced (and envious) of the rumours, the devil went to find out for himself whether or not Jack lived up to his vile reputation.
Typical of Jack, he was drunk and wandering through the countryside at night when he came upon a body on his cobblestone path. The body, with an eerie grimace on its face, turned out to be the devil himself. Jack realized that this was his end; Satan had finally come to collect his malevolent soul. So Jack made a last request: he asked the devil to let him drink ale before he departed to Hell. Finding no reason not to acquiesce the request, Satan took Jack to the local pub and supplied him with many alcoholic beverages. Upon quenching his thirst, Jack asked Satan to pay the tab for the ale, much to his surprise because he didn't carry any money. Jack convinced him to turn himself into a silver coin with which to pay the bartender and change back when he's not looking. Satan did so, impressed upon by Jack's unyielding nefarious tactics. Shrewdly, Jack stuck the now transmogrified Satan (coin) into his pocket, which also contained a crucifix. The crucifix's presence kept the devil from escaping his form. This coerced Satan to agree to Jack's demand: in exchange for his freedom, he had to spare Jack's soul for ten years.
Ten years after the date Jack originally struck his deal, he naturally found himself once again in the devil's presence. Jack happened upon Satan in the same setting as before and he seemingly accepted it was his time to go to Hell for good. As Satan prepared to take him to Hell, Jack asked if he could have one apple to feed his starving belly. Foolishly, Satan once again agreed to this request. As he climbed up the branches of a nearby apple tree, Jack surrounded its base with crucifixes. Satan, frustrated at the fact that he had been entrapped again, demanded his release. As Jack did before, he made a second demand: that he will never take his soul to Hell. Having no choice, the devil agreed and was set free.
Eventually the drinking took its toll on Jack, and he died. Jack's soul prepared to enter heaven through the gates of St Peter, but he was stopped. Jack was told by God that because of his sinful lifestyle of deceitfulness and drinking, he was not allowed into Heaven. Jack then went down to the Gates of Hell and begged for admission into the underworld. Satan, fulfilling his obligation to Jack, could not take his soul. He gave Jack an ember to light his way. Jack is doomed to roam the world between the planes of good and evil, with only an ember inside a hollowed turnip ("turnip" in this context referring to a large rutabaga) to light his way.
Irish families told the tale and began to put carved out turnips in their windows to prevent Stingy Jack and other ghouls from entering the home. Some had scary faces carved into them to frighten away any comers.
Once the tradition hit the United States, people soon realized that the pumpkin, native to the states, was an ideal fruit for carving. That's why you see jack-o'-lanterns on porches and in windows around Halloween.
Article by ZME Science & Wikipedia