Traffic light

Signalling device to control competing flows of traffic

Traffic lights, traffic signals, or stoplights – also known as robots in South Africa, Zambia, and Namibia – are signalling devices positioned at road intersections, pedestrian crossings, and other locations to control the flow of traffic. Traffic lights usually consist of three signals, conveying meaningful information to road users through colors and symbols, including arrows and bicycle symbols. The usual traffic light colors are red to stop traffic, amber to signal a change, and green to allow traffic to proceed.

From Wikipedia, under CC BY-SA. More on occurri.