where is the green light on a traffic light
Traffic light Aspect is a term referring to the light that faces the drivers. A typical vertical traffic signal has three aspects, or lights, facing the oncoming traffic, red on top, yellow below, and green below that. Generally one aspect is illuminated at a time. In some cases, a fourth aspect, for a turn arrow for example, is below the three lights or aspects in more complicated road traffic intersections.
Automotive lighting The colour of light emitted by vehicle lights is largely standardised by longstanding convention. It was first codified in the 1949 Vienna Convention on Road Traffic and later specified in the 1968 United Nations Convention on Road Traffic.[5][6] With some regional exceptions, lamps facing rearward must emit red light, lamps facing sideward and all turn signals must emit amber light, while lamps facing frontward must emit white or selective yellow light. No other colours are permitted except on emergency vehicles.