The lighting of the Christmas tree is a very important part of the holiday season. It is usually done at the start of December, on the first day of Advent, which is a period of waiting and preparation before Christmas Day. The Christmas tree is often decorated with lights, ornaments, and garlands, and the lighting of the tree marks the beginning of the festive season. It is a time of celebration and joy, when families come together to enjoy the beauty of the tree and to share in the spirit of Christmas.