A traffic light system is an electronic device that assigns rights of way at an intersection or crossing road by mean of displaying the standard red, yellow, green and pedestrian crossing coloured indications. A traffic light, also known as a traffic signal, stop light, stop-and-go light, is a signalling device positioned at a road intersection, pedestrians crossing, or other locations. It indicates when it is safe to drive, ride, or walk using a universal colour code and a precise sequence, for those that are colour blind. To facilitate the case of transportation in modern society, a wider network of roads are built with many intersections which will reduce traffic jam. Such jam will lead to waste of time and subsequently affect the economy. Road traffic control efforts have been made at traffic junctions using human beings (security officer e.g. policemen). This could have been an efficient way of traffic control but it has a major limitation of being expensive and bedevilled due to human error.
Adaptive time control has been tried which is determined by programming different traffic situation. Such methods cannot take care of priority demand of traffic use, for example, the case of emergency, fire service etc. Hence, the needs to have control structure that takes these emergencies into consideration.