Christmas, also known as Christmas Day or Christmastide, is an annual holiday falling on December 25 that honors and celebrates the birth of Jesus of Nazareth. His birth, which is the basis for the transcultural Western calendar, has been determined by modern historians as having occurred between 8–4 BC, and is traditionally told to have taken place in a stable within the city of Bethlehem. The specific date of celebration for Jesus' birth is traditional, and is generally believed to have been influenced by the dates of pre-Christian festivals usually the Roman festival of Dies Natalis Solis Invicti rather than having been based on historical data or reference.

Modern customs of the holiday include gift-giving, church celebrations, and the display of various decorations including the Christmas tree, lights, mistletoe, nativity scenes and holly. The jolly mythological figure Santa Claus, or Father Christmas, is also a major aspect of Christmas; he is traditionally believed by millions of children as being a bringer of gifts on or before Christmas Day. Santa is generally believed to be the result of the syncretization of Saint Nicholas with elements from Germanic paganism and Christian mythology, and owes his modern appearance mostly to 19th century media.