In this intriguing episode of “ok now you know,” host Joe Garner delves into the fascinating history of one of the most familiar traffic signs—the stop sign. As he traces its origins back to the bustling streets of early 20th century Detroit, Joe uncovers the inventive spirit of Harold Jackson, a police sergeant whose practical solution to a dangerous intersection marked the birth of the iconic stop sign.

Joe discusses how the initial plywood sign, designed with an octagonal shape to draw attention, quickly caught on. Within a year, Michigan had adopted this vital road safety measure, originally featuring black letters on a white background. The journey of the stop sign did not end here; as automobiles became commonplace, the need for a standardized design surfaced. In 1922, the American Association of State Highway Officials selected the octagon for its distinctiveness, ensuring visibility from all perspectives. The episode further explores the evolution of the stop sign’s color, transitioning from white to yellow, and finally to the globally recognized red in 1968, as solidified by the Vienna Convention on Road Signs and Signals. This standardization marked a significant leap towards synchronized international road safety protocols.