Everyone has heard of Halloween but no one exactly knows when it started it was first known to start 2000 years ago from the ancient Celtic festival of Samhain. The Celts were mostly in the area that is now Ireland, the United Kingdom and Northern France.
Now, what are some of the traditions that we follow today? We follow Carving Halloween Jack-O'-Lanterns and place them around our houses for decoration! Why do we do this? We do this because, in the 8th century CE, the Roman Catholic Church moved All Saints' Day, a day celebrating the church's saints, to November 1. This meant that All Hallows' Eve (or Halloween) fell on October 3. The town folk made this tradition and it was then quickly made into Halloween, and we've been carving pumpkins.
Another tradition that everyone does is dress up. We do this because it was known that the veil between our world and the spirit world was at its weakest during the birth of Halloween and because of this, people feared evil visiting them. To hide from the spirits, they would dress up in disguises. This has since changed into a day to flaunt any costumes.
The last worldwide tradition that I certainly like is trick or treating! It started when beggars knocked on doors asking for food. They would say prayers for the dead in exchange for food. A while later if then turned into maybe singing songs or reciting poems for food and eventually by the time it crossed the seas to America, the method of going door to door was now about tricks or treats!