Christmas Day is a Christian holiday that takes place on December 25th which is presumed to originally take place 25 December 1 BC, but no one really knows if that's accurate. It is a holiday that takes place in many different countries around the world.
Christmas trees and red, green and gold decorations are extremely popular during this time of year for decor and presents. Most people celebrate with mistletoe and caroling around the house or neighborhood.
The holiday started out as a Christian tradition to celebrate the birth of Christ and the Winter Solstice back in the Holy Roman Empire. Then the secular ideas of Santa and gift giving became part of the holiday celebration.