What signals caution during taxiing on the runway?

Yellow taxiway markings signal caution during taxiing on the runway. These markings indicate the designated paths for aircraft to follow while on the ground, guiding pilots in safely navigating to and from runways and taxiways. The yellow color is standardized in aviation to alert pilots to areas of potential concern, helping to enhance situational awareness and reduce the risk of runway incursions or mishaps.

In contrast, other signals serve different purposes. Red stop signals indicate that an aircraft must stop immediately, while green takeoff lights signify that it is safe to proceed for takeoff. White runway lights are primarily used to delineate the edges of the runway, assisting with visibility during takeoff and landing rather than providing a cautionary signal during taxiing.