Traffic signals are considered to be the best solution for traffic control at large intersections and crossings right-turning of which a large amount of traffic has to come across several conflict points and hence there is a possibility of accidents.
In the development of urbanization, a traffic motorization and traffic controlling by signal lights must not be dispensed with. This paper describes the effect of traffic control lights on the traffic flow such as active, passive, cost, and environmental effects. It is an important requirement to adopt such a traffic control requiring the least of sacrifices both from the part of traffic and persons partaking in urban traffic.
In general, several constant time programs can be practically applied. However, traffic light can only be operated with one or two programs.