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Giving the Green Light

Giving the Green Light

When we drive on the road, we have to stay on one side, and wait our turn where roads cross. Stop signs help, but really busy crossings need traffic lights. The very first electric traffic light was invented in 1912 by Lester Wire, but his light had just two colors: red for stop and green for go. Then in 1920, Detroit cop William Potts built one with 3 colors (red, orange and green). People have tried other designs, but the three-color light is what keeps most of us from crashing into each other today.

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