Christmas Day is always celebrated on December 25. In 2014, December 25 falls on a Thursday, and in 2015, it falls on a Friday. Christmas is a Christian holiday celebrating the birth of Jesus Christ.
Christmas has been celebrated on December 25 since the fourth century, although the true date of Christ's birth is unknown. It was established as December 25 by Pope Julius I, and it aligns with the Roman pagan holiday celebrating "the birth of the invincible sun." In addition, Christmas is frequently celebrated by non-Christians as a time for gift-giving, caroling and feasting. Some symbols of Christmas, such as using an evergreen tree as the Paradise tree and decorating it, may have originally come from the pagan tradition of using evergreen branches to symbolize life.