Get the Green Light

Origin

The vibrant, unmistakable signal to 'go' emerged from the burgeoning world of railway and later road transportation. Early railway signals, often using colored lamps or flags, established red for danger and green for safety or clear passage. As automobiles became ubiquitous in the early 20th century, the first electric traffic lights, like the one installed in Cleveland in 1914, adopted this established color code. Drivers learned that a green light meant freedom to move forward, a clear path ahead. This straightforward, universal symbol of approval quickly transcended the intersection, lending its vivid imagery to our everyday language as a powerful metaphor for receiving authorization to proceed with any endeavor.