What is Garrett Morgan's most important invention?

Garrett Morgan's most important invention is the three-position traffic signal, which he patented in 1923. This innovative device improved road safety by introducing a warning light, allowing drivers to stop, go, or prepare to stop, thus reducing accidents at intersections. Morgan's invention laid the groundwork for modern traffic lights, significantly enhancing urban traffic management and pedestrian safety. His contributions extend beyond traffic control, as he was also known for his work in gas masks and hair care products.