Evolution of Traffic LightsIntroductionTraffic lights are ubiquitous in the United States and much of the developed world. There is no doubt that they play a huge role in our transportation system by maintaining road safety and reducing congestion. Although we use traffic lights every day, few people know their origin and the remarkable technological innovations that contributed to their development. This essay explores the history of traffic lights and their evolution over time. Origins in Europe Traffic lights have a very long history. Evidence shows that in ancient Rome in 230 BC, mile markers were used to indicate direction to pedestrians. The first device that somewhat resembled today's traffic lights was called a semaphore, which was about 22 feet tall and had two arms: when the arms were placed in a horizontal position that signaled "stop" and when They were tilted at 45 degrees, which meant "move with caution." The first semaphore was manually operated and was installed in 1868 at the intersection of George and Bridge Streets in London (Mueller, 1970; Bullock and Urbanik, 2000). Later, gas lamps were added to the semaphores, allowing them to be used at night. People had high hopes for these innovative devices, but in 1872 Parliament suddenly abolished them all. There were two main reasons for their withdrawal. First, a terrible semaphore gas explosion incident occurred in 1872, injuring two policemen and killing the third. The second reason was that semaphores were expensive to make. Although engineers worked quickly to change the design to make them safer and cheaper, they were not widely adopted until the rise of the automobile (Mueller, 1970). The rise of automobiles and... traffic jams...... middle of paper.... ..traffic lights in real time. This system could significantly reduce the installation and maintenance costs of road sensors. Some of the biggest issues with this system currently concern privacy and user participation (Mohan et. al, 2008). ConclusionTraffic signals have truly come a long way since their development in Europe in the late 19th century. It's simply remarkable how much traffic lights have evolved in about 100 years. They became more efficient with the introduction of automation in the 1920s and then again with the addition of microprocessors in the 1970s. It is difficult to predict what the next new technologies will be in the decades to come. Could it be smartphones? Or maybe machine learning? Or a combination of both? Either way, traffic lights will only get better and improve the safety and quality of drivers' driving experience..