Pedestrian

Pedestrian signals began to appear at heavily trafficked intersections in the 1920s. The first actuated pedestrian signal - a signal that is activated by a push button - was installed in Baltimore in 1929.

The Manual on Uniform Traffic Control Devices (MUTCD) published standards for pedestrian signals in 1935. They advised the use of a two circular signals, one with the word "Walk" and the other "Wait."

Revisions to the MUTCD in 1939 advised the use of rectangular pedestrian signals, having white backgrounds with the words "Walk" and "Wait" in black lettering. However, the circular pedestrian signals were still used frequently.

In 1948, the "Walk" and "Wait" signals were officially changed to "Walk" and "Don't Walk."

The color scheme for pedestrian signals was updated in the 1961 MUTCD. The "Walk" could be green or white on a black background, and the "Don't Walk" could be red or orange on a black background.

The use of symbols instead of words for pedestrian signals was approved in the 1978 MUTCD.