Provide two traditions of Halloween.

Jack-o'-lantern: The term "Jack-o'-lantern" came from an Irish folk tale of the 18th century. Jack was an Irishman. He had tricked the Devil into climbing an apple tree. He then cut a cross symbol in the tree trunk, thus trapping the Devil in the branches. When Jack died, he was unable to again access to Heaven because of his meanness. The Devil, having a long memory, would not allow him into Hell. So he was forced to walk the earth endlessly. The devil took pity on him and gave him a piece of coal to light his path. Jack put it inside a hollowed-out turnip that he had been eating.

Trick-or-treating is a customary practice for children on Halloween in many countries. Children in costumes travel from house to house in order to ask for treats such as candy (or, in some cultures, money) with the question "Trick or treat?".

from: http://www.religioustolerance.org/hallo_cu.htm
http://en.wikipedia.org/wiki/Trick-or-treating