Originally candles were used to light the tree. Martin Luther was supposed to have been the person who started the passion for lights on a tree in the 16th century when he wanted to show worshippers the effects of the wonder of stars twinkling through a forest of evergreen trees.
The candles were held in place by either gluing melted wax to a tree branch or using pins to hold the candle. Around 1900, candle holders were being used, and by 1915 small lanterns and glass balls became a means of holding the candles in place.
Then, in 1882, Thomas Edison's assistant, Edward Johnson, came up with the idea of electric Christmas lights. He lit up a Christmas tree in New York City with 80 small electric bulbs. Within 20 years, stores were displaying electric lights and they were being mass produced and sold to customers.
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