The Traffic Light: A Hero's Other InventionHow a dramatic rescue led to safer streets for everyone.

From the show

The Secret Life of Objects

The yellow light that prevents daily collisions has a heroic origin. After witnessing a horrific crash, Garrett Morgan—an inventor and son of freed slaves—designed the revolutionary three-position traffic signal. This wasn't his first life-saving creation; he had already used his patented 'safety hood' to rescue men from a collapsed tunnel. Morgan's T-shaped signal included an all-directional stop, the precursor to the modern yellow light, allowing pedestrians to cross safely. He sold the patent to General Electric, forever changing road safety.