Halloween is a yearly celebration observed in a number of countries on the eve of the Western Christian feast of All Hallows' Day. It initiates the triduum of Hallowtide, the time in the liturgical year dedicated to remembering the dead.
Feasts and observances
Dressing up; going to parties; carve a pumpkin; trick-or-treating; costume parties; making jack-o'-lanterns; lighting bonfires; divination; apple bobbing; visiting haunted house attractions
Western Christians and many non-Christians around the world