Observance of Christmas by country in the context of "Christmas card"

Christmas is an annual festival commemorating the birth of Jesus Christ, observed primarily on December 25 as a religious and cultural celebration among billions of people around the world. A liturgical feast central to Christianity, Christmas preparation begins on the First Sunday of Advent and it is followed by Christmastide, which historically in the West lasts twelve days and culminates on Twelfth Night. Christmas Day is a public holiday in many countries, is observed religiously by a majority of Christians, as well as celebrated culturally by many non-Christians, and forms an integral part of the annual holiday season.

The traditional Christmas narrative recounted in the New Testament, known as the Nativity of Jesus, says that Jesus was born in Bethlehem, in accordance with messianic prophecies. When Joseph and Mary arrived in the city, the inn had no room, and so they were offered a stable where the Christ Child was soon born, with angels proclaiming this news to shepherds, who then spread the word.

Christmas Eve is the evening or entire day before Christmas, the festival commemorating the birth of Jesus. Christmas Day is observed around the world, and Christmas Eve is widely observed as a full or partial holiday in anticipation of Christmas Day. Together, both days are considered one of the most culturally significant celebrations in Christendom and Western society.

Christmas celebrations in the denominations of Western Christianity have long begun on Christmas Eve, due in part to the Christian liturgical day starting at sunset, a practice inherited from Jewish tradition, and based on the story of Creation in the Book of Genesis: "And there was evening, and there was morning—the first day." Many churches still ring their church bells and hold prayers in the evening; for example, the Nordic Lutheran churches. Since tradition holds that Jesus was born at night (based in Luke 2:6-8), Midnight Mass is celebrated on Christmas Eve, traditionally at midnight, in commemoration of his birth. The idea of Jesus being born at night is reflected in the fact that Christmas Eve is referred to as Heilige Nacht (Holy Night) in German, Nochebuena (the Good Night) in Spanish and similarly in other expressions of Christmas spirituality, such as the song "Silent Night, Holy Night".

Christmas traditions include a variety of customs, religious practices, rituals, and folklore associated with the celebration of Christmas. These traditions are diverse in their origins and nature, with some having an exclusively Christian character with origins from within the religion. Other traditions are considered more cultural or secular in nature and have originated outside Christian influence. Christmas traditions have also changed and evolved significantly in the centuries since the Christmas holiday was first instituted, with celebrations often taking on an entirely different quality depending on the period and geographical region.