Trick-or-treating is a Halloween tradition that started a long time ago for a few different reasons, and it's a bit like a game.

A long, long time ago, people believed that on Halloween night, ghosts and other spooky creatures would come out to play tricks on them. So, to protect themselves, they dressed up in costumes to look like ghosts themselves. They thought this would fool the real ghosts, and the ghosts wouldn't play tricks on them.

Then, people started going from house to house in their costumes, asking for treats like candies, fruits, or nuts. They did this because they believed that by giving treats to the people in costumes, the ghosts would leave them alone and not play tricks on them.

Over time, this tradition turned into the modern trick-or-treating we know today. Kids dress up in costumes, go to their neighbors' houses, and say, "Trick or treat!" The neighbors give them yummy candies and treats to make sure the kids don't play tricks on them.

So, trick-or-treating is a fun way to celebrate Halloween and remember the old idea of dressing up to protect yourself from spooky spirits while also getting some delicious treats!