Halloween originated from the ancient Celtic festival of Samhain, where the Celts believed the ghosts of the dead returned and caused chaos. They wore masks and danced to scare away the ghosts. Halloween traditions result from a mix of Native American and European autumn festivals involving storytelling, dancing, games, foods and more. Modern Halloween activities include carving pumpkins, decorating with spiders and skeletons, wearing costumes, and trick-or-treating where children dress up and go door-to-door requesting treats.