This tradition was later brought to the North American continent by Irish immigrants who were escaping the Potato Famine in their homeland. In addition to the festival itself, the immigrants brought several customs with them, including one of the symbols most commonly associated with Halloween -- the Jack 'O Lantern.
According to Irish folklore, there once lived a man named Jack who was known for being a drunk and a prankster(顽皮的人, 爱开玩笑的人). One night Jack tricked the devil into climbing a tree, and quickly carved an image of a cross on the trunk, trapping the devil. Jack then made him promise that, in exchange for letting him out of the tree, the Devil would never tempt him to sin again. He reluctantly agreed, but was able to exact his revenge upon Jack's death. Because of his mischievous ways in life, Jack was barred from entering heaven and because of his earlier trick, he was also barred from hell. So he was doomed to wander the earth until the end of time, with only a single ember(灰烬, 余烬) (carried in a hollowed out turnip.[植]芜箐, 芜箐甘蓝) to warm him and light his way.