This orange pumpkin Halloween party invitation depicts a popular American holiday for children and adults. Every year on October 31st, it is observed. Children dress up in costumes and go from house to house after dark, knocking on doors and saying, trick or treat! The children are then given treats such as candy. Costumes can be frightening. There will be many witches, monsters, ghosts, and vampires, but there may also be many children dressed as fairies or princesses. It is also a time when people throw Halloween parties where they can play fun games like apple bobbing, go through a haunted house, or have a costume party. On Halloween, you'll also see a lot of jack-o'lanterns.