Traffic lights, also known as traffic signals, traffic lamps, traffic semaphore, signal lights, stop lights and robots,and also known technically as traffic control signals are signalling devices positioned at road intersections, pedestrian crossings and other locations to control competing flows of traffic. The first manually operated gas lit traffic light was installed in 1868 in London, though it was short-lived due to explosion. The first safe, automatic electric traffic lights were installed in the United States starting in the late 1890s.
Garrett Morgan's curiosity and innovation led to the development of many useful and helpful products. Among his inventions was an early traffic signal. After witnessing a collision between an automobile and a horse-drawn carriage, Morgan was convinced that something should be done to improve traffic safety. Morgan was one of the first to apply for and acquire a U.S. patent for a traffic signal. The patent was granted on November 20, 1923. Morgan later had the technology patented in Great Britain and Canada. He also invented a zigzag stitching attachment for manually operated sewing machine. In 1916, Morgan made national news for using a gas mask he had invented to rescue several men trapped during an explosion in an underground tunnel beneath Lake Erie. After the rescue, Morgan’s company received requests from fire departments around the country that wished to purchase the new masks.