Are traffic lights synchronized for mutual passage on urban roads?

[VanFernando]

This depends on the road traffic conditions. In some cities with heavy traffic flow, the timing of each traffic light may vary. Classification of traffic lights: Traffic signals are categorized into motor vehicle signals, non-motor vehicle signals, pedestrian crossing signals, directional indicator signals (arrow signals), lane signals, flashing warning signals, and railway crossing signals. Colors of traffic lights: Initially, there were only red and green colors. After improvements, a yellow light was added. The red light means stop, the yellow light means prepare, and the green light means go.