The holiday season must be an especially happy time for power companies: It seems that every house on the block has electric candles in the windows, strings of lights on the bushes or a glowing Christmas tree by the living room window. Across a range of faiths, lights are a symbol of the holidays. For example, Christians who celebrate Christmas hang lights, or line their streets with illuminaria, which symbolically guide the Christ child to earth from Heaven.
Holiday lighting is a tradition that precedes electric lights by centuries. But with a wide range of bulb sizes, colors and arrangements, nearly all revelers now practice this holiday tradition with bulbs instead of traditional -- and more fire-prone -- candles.