Tomorrow is October, 31 which is not just any day of the year. Halloween is thought to have originated from the Celtic holiday Samhain, which was celebrated on November, 1. It was believed that the day before Samhain the dead would turn into ghosts. To celebrate people would light bonfires and wear costumes or masks to be mistaken for fellow ghosts. The christian church turned Samhain into All Saints Day and the night before, October, 31 was called All Hallows Eve which later became Halloween. Nowadays Halloween is celebrated with Trick-or-Treating and lots of carved pumpkins.
When I was younger I used to go Trick-or-Treating but we lived in a very small town so we would never get a lot of candy, which was quite discouraging. I never really thought that Halloween originated in America, because it is, in fact, the second most successful commercial holiday in the United States after Christmas. I guess most people think that it actually originated in America but to be honest I also never knew it was an ancient Celtic holiday before informing myslef. During my research I found out that Irish immigrants brought their traditions and festivities of Samhain to America which then resulted into Halloween being celebrated all over the world. Personally, I feel like modern day Halloween no longer has much to do with old traditions anymore. It just seems to be another 'holiday' for big companies to make money. About 6 Billion dollars are spent every year, e.g., in America on that day. I have to point out though that I still like Halloween very much. It's nice to have all the scary Halloween specials on TV, like the Simpsons Halloween episodes and it's also fun to dress up as something scary and then go to a Party.