Final answer:
A flashing yellow light or arrow in traffic signals indicates caution and drivers should slow down and exercise caution.
Step-by-step explanation:
A flashing yellow light or arrow in traffic signals indicates caution. It is typically used to alert drivers to proceed with caution through an intersection or to be prepared to stop if necessary. Unlike a red light, a flashing yellow light does not require drivers to come to a complete stop, but they should slow down and exercise caution.