Christmas, also referred
to as Christmas Day, is an annual holiday celebrated on December 25
that commemorates the birth of Jesus of Nazareth.
The day marks the beginning of the larger season of Christmastide, which lasts twelve
days. The nativity of Jesus, which is the basis for the anno Domini
system of dating, is thought to have occurred between 7 and 2 BC.
December 25 is not known to be Jesus' actual date of birth, and the
date may have been chosen to correspond with either a Roman festival
or the winter solstice.