Christmas is Christian holiday that celebrates the birth of Jesus Christ. For millions of Christians throughout the world it is the happiest and the busiest time of the year. People of different countries celebrate Christmas in various ways. A Christmas tree is one of the main symbols of Christmas in most homes. Relatives and friends may join in trimming the tree with lights, tinsel, and colourful ornaments. Presents are placed under the tree. On Christmas Eve or Christmas morning, families open their presents.