The earliest Christmas trees were decorated with candles. Glued to the tree with wax or attached with pins, they were something of a fire hazard.
The invention of electricity transformed the Christmas tree. The first one lit by electric bulbs was set up in New York City in 1882 by Edward Hibberd Johnson.
He was an associate of Thomas Edison and he placed the tree in the window of his house. It had 80 red, white and blue bulbs powered by a generator.
The first sets of Christmas lights were very expensive, but shops started to use them in their window displays. Then, as electrification spread, so did the trend.
The record for the most Christmas lights on a house belongs to the Gay family from LaGrangeville, New York. In 2014 they hung an astounding 601,736 lights on their home.