Halloween (also spelt Halloween) is an annual festival celebrated on October 31. It has roots in the Celtic (Celtic paganism) festival of Samhain and the Christian holy day of All Saints, but is today largely a secular celebration.

Halloween activities include trick-or-treating, wearing costumes (Halloween costume) and attending costume parties (Costume party), carving jack-o-lanterns, ghost tours (Ghosts in European culture), bonfires, apple bobbing, visiting haunted attractions, pranks, telling scary stories, and watching horror films.