Halloween...that's celebrated on every October 31 in most of the western country, especially USA.

I always wonder why is there Halloween, what's the history behind it...so I did some googling and here's what I found from http://en.wikipedia.org/wiki/Halloween

Halloween has origins in the ancient festival known as Samhain (pronounced sow-in or sau-an), which is derived from Old Irish and means roughly "summer's end". This was a Gaelic festival celebrated mainly in Ireland and Scotland.

The festival of Samhain celebrates the end of the "lighter half" of the year and beginning of the "darker half", and is sometimes[6] regarded as the "Celtic New Year".

The ancient Celts believed that the border between this world and the Otherworld became thin on Samhain, allowing spirits (both harmless and harmful) to pass through. The family's ancestors were honoured and invited home whilst harmful spirits were warded off. It is believed that the need to ward off harmful spirits led to the wearing of costumes and masks. Their purpose was to disguise oneself as a harmful spirit and thus avoid harm.

Now..ever heard of Jack-O-Lantern? All I know that's what people used referring to the carved pumpkin with candle lit inside it. Here's what I found from the same article.

The name jack-o'-lantern can be traced back to the Irish legend of Stingy Jack, a greedy, gambling, hard-drinking old farmer. He tricked the devil into climbing a tree and trapped him by carving a cross into the tree trunk. In revenge, the devil placed a curse on Jack, condemning him to forever wander the earth at night with the only light he had: a candle inside of a hollowed turnip. The carving of pumpkins is associated with Halloween in North America where pumpkins are both readily available and much larger- making them easier to carve than turnips.

Sooo.....that's why now on every Halloween season, people carve the pumpkin instead of Turnip, all thanks to the American for not having Turnip

Now you ask...why in the present time there's more Halloween decoration here in North America aside from the old Jack-O'-Lantern? All thanks to the Hollywood that now people in North America associates Halloween with horror creatures from the films such as Frankenstein, Dracula, Vampires, Zombies, Skeleton, Bats, Crows, Ghost, the Mummy, Grim Reaper, and many more.

As for trick-or-treat tradition is quoted here:
Trick-or-treating is a customary celebration for children on Halloween. Children go in costume from house to house, asking for treats such as candy or sometimes money, with the question, "Trick or treat?" The word "trick" refers to a (mostly idle) threat to perform mischief on the homeowners or their property if no treat is given. In some parts of Ireland and Scotland children still go guising. In this custom the child performs some sort of show, i.e. sings a song or tells a ghost story, in order to earn their treats.

SO..there you go...a brief and quick history of Halloween, just in case you are wondering.

As for me...I shall be celebrating this Halloween with a bunch of our friends' children by 'guiding' them to do some Trick-or-Treat at people' house. Hey..maybe we can help them eat some of the candies and chocolate too, eh?!