Christmas lights is an important part of Christmas decorations. It is not only bright and colorful, but also adds atmosphere and a festive atmosphere to winter. Christmas lights are usually divided into incandescent lamps, light-emitting diode (LED) lamps and laser lamps according to their composition. Incandescent lamps are the most common type of Christmas lights, usually made of glass or plastic, and controlled by a switch. LED lamps are energy-saving, environmentally friendly and have a long life, but their cost is relatively high. Laser lights use lasers to project images or patterns onto a wall or other surface. Christmas lights bring people a holiday joy. Whether it is tree or courtyard decoration, or combined with music to achieve an interesting lighting effect, people can enjoy the fun of Christmas. In addition, it is important to maintaining the PCB relay when installing Christmas lights. Quality inspection of Christmas lights is also essential to ensure safe use. In conclusion, Christmas lights play an important role in the atmosphere, decorating and celebrations of Christmas, so it needs to be used in a safety and healthy way.