It is hard to imagine how residents of megacities would do without such familiar cars now. They are already in every family, and in some it is impossible to live without two or three cars. And this is not surprising, because every day we have to visit different places in cities almost simultaneously. Such a stream of cars on the roads of a metropolis must obey clear rules, otherwise all traffic will turn into chaos. One of the most important traffic controllers to whom all drivers must obey is the traffic light.
What is a traffic light?
A traffic light is a device that, with the help of light signals, regulates the flow of traffic. It can be not only cars, water and rail transport are subject to traffic lights.
The very name of this device familiar to us came from the Greek language and literally means "carrying light."
Where did the traffic light come from?
The first traffic light appeared a hundred and fifty years ago. Its inventor was a British engineer who had been developing semaphores for railways all his life. Therefore, it is not surprising that the first traffic light was an almost complete copy of the railway semaphore. He had several arrows that were set in motion by man. At night, when the shooter was not visible, the traffic light turned into a gas-powered lantern. The lantern was two-color, it was then that the familiar signals of red and green were fixed. Subsequently, they became the basis for automatic traffic lights.
The first automatic traffic lights
A gas-based motion control device was very dangerous. In history, there have been recorded cases when a gas lamp exploded and became the cause of injuries to police officers who controlled the work of a traffic light. Therefore, by the beginning of the twentieth century, models of automatic traffic lights appeared. Not all devices were convenient. For example, on one of them words were put on which drivers should be guided. In other cases, the device had the usual two colors, but was controlled by a policeman from a distance. It was then that the green arrow was first used to turn left.
The first electric traffic light was installed in America in the twenties of the last century. He had three colors and worked on the principle of priority.
Traffic lights in the USSR
Until the thirties there were no traffic lights on the roads of the USSR. The first device was installed in Leningrad and gradually spread to the cities of the country. The traffic light had two colors, located differently than now. Only in the sixties were international rules adopted governing the production and appearance of traffic lights.
Car traffic lights
Despite the fact that there are now more than nine types of devices that regulate the flow of traffic, the most famous and popular are traffic lights. They can be horizontal and vertical, and also have two or three colors. In some cases, yellow is allowed to be replaced with orange, which can be seen on most Russian traffic lights.
A car traffic light also regulates pedestrian movements if there are no other devices at the intersection. Most often, it has three round signal parts, but some models are supplemented by a light panel with a time report and sections where the green arrow is depicted.
Traffic Signal Designations
Traffic signals are the same throughout the world. Their designations are taught from childhood:
- red color prohibits travel;
- yellow is forbidden, but allows travel in case of emergency braking;
- a green signal allows movement in the indicated direction.
In some cases, the yellow signal lights up simultaneously with the red one and indicates that the green traffic light will light up soon.
Green arrow - what is it?
With the increase in the number of cars, it became necessary to create traffic lights with additional sections. They are placed at the busiest and most difficult intersections of the city. It is not difficult for experienced drivers to deal with all the subtleties of movement when the green arrow is on. But for beginners it is difficult, it is difficult for them to understand when it is possible to start moving in the direction, and when in addition to the green signal you need to wait for the arrow.
Drivers learn all these wisdom before they get the right to drive a car. But the cases are completely different. For example, you got rights in a small town, where you ran into your main watch. In such settlements, there are practically no intersections where the green arrow at the traffic lights causes difficulties with understanding. But when moving to a larger city, a driver who considers himself to be quite experienced may encounter problems and create emergency situations on the roads.
