The yellow color was adopted as the standard color for school buses at a national conference of school transportation in 1939. School buses are yellow to ensure they are easily visible in dim or bright light. The bright yellow school bus color is meant to get the attention of pedestrians and drivers on the road. The yellow color makes it easy for school buses to be seen from a distance, even in foggy weather. Another reason why buses are yellow is that safety laws in some areas require that the buses be yellow, making them one of the most recognizable vehicles on the road.