Christmas lights (holiday decoration)

Christmas lights (also known as fairy lights) are lights used for decoration in preparation for Christmas and for display throughout Christmastide. The custom goes back to the use of candles to decorate the Christmas tree in Christian homes in early modern Germany. Christmas trees displayed publicly and illuminated with electric lights became popular in the early 20th century. By the mid-20th century, it became customary to display strings of electric lights as along streets and on buildings Christmas decorations detached from the Christmas tree itself. In the United States, it became popular to outline private homes with such Christmas lights in tract housing beginning in the 1960s. By the late 20th century, the custom had also been adopted in non-western countries / regions, notably in Japan and Hong Kong.

In many countries, such as Sweden, people start to set up their Christmas lights, as well as other Christmas decorations, on the first day of Advent. In the Western Christian world, the two traditional days when Christmas lights are removed are Twelfth Night and Candlemas, the latter of which ends the Christmas-Epiphany season in some denominations. Leaving the decorations up beyond Candlemas is historically considered to be inauspicious.

The Christmas tree was adopted in upper-class homes in 18th-century Germany, where it was occasionally decorated with candles, which at the time was a comparatively expensive light source. Candles for the tree were glued with melted wax to a tree branch or attached by pins. Around 1890, candleholders were first used for Christmas candles. Between 1902 and 1914, small lanterns and glass balls to hold the candles started to be used. Early electric Christmas lights were introduced with electrification, beginning in the 1880s.

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