If people drove around without guidance or coordination in busy places like Kigali, there would be utter chaos. Accidents would occur, drivers would get into screaming matches or fist fights, and some lives would be lost. That is why traffic lights are an important invention.

John Peake Knight, a British railway engineer was the visionary who came up with the idea of traffic lights back when the most sophisticated mode of transport was a horse carriage. According to Science ABC a knowledge dissemination platform, the first traffic lights were made of wooden semaphores and lit by gas. They were installed outside the houses of parliament in London on December 10, 1868.

A month later, there was a gas leak and one of the lights exploded in the face of the police officer who was on duty. Because of this, traffic lights were seen as a health hazard and it was decided that their installation should be stopped. This is according to Live Science, an information sharing platform.

For several decades, there were no traffic signals. Then in 1912, Lester Farnsworth Wire who was a director of traffic safety in Utah drew inspiration from the design of a birdhouse to make traffic lights. According to Live Science, a web-based knowledge sharing platform, the lights comprised of two holes, one with a green bulb and another one with a red bulb. They were also operated manually by switching either bulb on or off.

The three-color traffic signals that drivers use today were the brainchild of American policeman William L. Potts. The invention was made in 1920 and it was an adoption of the railway signals. Like its predecessors, the red, green and yellow traffic signal required a person to flip a switch to change the light. According to Today I Found Out an online education site, manual operation proved tiring and costly.

In 1923, American inventor Garrett Morgan invented the automatic traffic lights. There were many others like Morgan who had thought of the same idea but he is credited with the invention because he patented it. This is according to Idea Finder, a web-based platform on information about ideas.

Automatic lights changed at fixed time intervals. This caused some people to grow impatient since they had to sit and wait even when there was no danger of colliding with other vehicles. In an attempt to solve this challenge, Charles Adler Jr. an inventor developed the idea of a signal which changed after the detection of vehicles’ honking. According to Science ABC, this didn’t work because it resulted in too much noise.

The invention of computers in 1960 resulted in a huge leap in traffic monitoring and control. Several other improvements such as cameras, countdowns, "walk” and "don’t walk” signs for pedestrians have been made over the years. They make it easy for people to go through cities that have an ever increasing number of vehicles on the road without the fear of chaos or danger.