Traffic signals are control devices which can alternately direct the traffic to stop and proceed at intersections using automatic red, yellow and green traffic light signals. They provide orderly movement of traffic and increase the traffic handling capacity of intersections, reduce accidents, and increase the safety of pedestrian crossings. Traffic Signals can operate in several different modes:
For the purpose of this training module, we will focus on Pre-timed Operation. Pre-timed signals are the simplest type of traffic signals, where the length of the cycle, phases, and all intervals are predetermined. To understand the basic concepts of pretimed signal timing click on "Background." For hands-on experience developing and implementing signal timing plans for case studies, click on "Exploration."