The stop sign was officially invented by Detroit police sergeant Harold “Harry” Jackson in 1914. Jackson created the first physical stop sign by cutting the corners off a rectangular piece of plywood and painting the word "STOP" on it to improve traffic safety at a busy intersection
. However, William Phelps Eno, known as the “Father of Traffic Safety,” played a critical role in popularizing and formalizing the use of stop signs. Eno was a pioneer in traffic control who developed many early traffic safety innovations, including traffic regulations, pedestrian crosswalks, and one-way streets. He proposed the concept of stop signs around the turn of the 20th century and helped establish traffic rules that laid the groundwork for modern road safety
. In summary:
- Harold “Harry” Jackson invented and installed the first physical stop sign in 1914 in Detroit.
- William Phelps Eno popularized the idea and helped formalize traffic safety rules, including the use of stop signs.
Thus, Jackson is credited with the first actual stop sign, while Eno is credited with the conceptual and regulatory development of stop signs and broader traffic safety
