The name "Christmas" is the acronym for "Christian Mass". Mass is a liturgy of the church. Christmas is a religious festival. We celebrate it as the birthday of Jesus and hence Christmas. On this day, all the Christian churches around the world hold special services. But many Christmas celebrations have nothing to do with religion. Exchanging gifts and sending Christmas cards all make Christmas a day of celebration.
Christmas commemorates the birth of Jesus on December 25, but no one knows the real birth date. In the nineteenth century, Christmas cards became popular, Santa Claus appeared, and Christmas became popular.
The year of Jesus' birth is unknown, but most archaeologists believe it should be the year in which the centuries were divided. But the correct date could not be determined, so in early Christianity the Roman Empire of Misrasu celebrated the birth of the Sun God on December 25 as Christmas Day.