Christmas or Christmas Day is a holiday celebrating the birth of Jesus, the central figure of Christianity. Aspects of celebration may include gift-giving, Christmas trees, display of Nativity sets, church attendance, the Father Christmas/Santa Claus myth, and family gatherings. Users of the Gregorian calendar observe the holiday on December 25. Some Eastern Orthodox Churches celebrate on December 25 by the Julian calendar, which currently corresponds to January 7 on the Gregorian calendar. These dates are merely traditional; the great majority of scholars agree that the actual birthdate of Jesus is unknown.