"Trick or Treat!" yup people say it when they want something from others such as candy or maybe another. If people can't give anything to people that asked for they want, they will threat you like write threat words in the window with the blood or.... they will kill you! But it wouldn't like that, so creepy.
Peoples celebrates Halloween with:
1. Halloween costume
2. Halloween foods and drinks
3. Watching scary movies
Much more you can do when halloween, yes scary things.