National Christmas Lights Day is observed worldwide on December 1. This holiday celebrates the tradition of decorating with Christmas lights, which have been a part of the holiday season for over a century. The first electrically-illuminated Christmas tree was created by Edward H. Johnson in 1882, marking the beginning of modern Christmas lights. Traditionally, Christmas trees were adorned with miniature candles, but these posed fire hazards, leading to the adoption of electric lights. On this day, people are encouraged to put up their Christmas trees and decorate their homes with lights, preferably opting for energy-efficient LED options. Many cities also host Christmas lights festivals, showcasing elaborate displays that attract tourists, such as the TSB Festival of Lights in New Zealand and the Magnificent Mile Lights Festival in Chicago. Celebrants often share their holiday experiences on social media using the hashtag #NationalChristmasLightsDay.