Why do traffic lights use red, yellow, and green only? The global standard that changed road safety forever
etimes.in / Jun 07, 2026, 19:26 (IST)
Traffic lights, a universal symbol of order, evolved from chaotic roads to controlled intersections. Red, chosen for its visibility in poor conditions, signals stop. Green, replacing confusing white, signifies go, offering psychological calm and high visibility. Yellow, introduced later, acts as a crucial transition, warning drivers to proceed with caution. This simple yet effective system dramatically improved road safety.