CHECKERED FLAG: Signifies the end of the practice session, qualification attempt or race. The race leader is declared the winner.
GREEN FLAG: Signals the start of the practice session, qualification attempt or race and all restarts after a caution or red-flag period.
YELLOW FLAG: The "caution flag," signals hazardous conditions on the track, and cars must slow immediately, maintain position and yield to track safety vehicles until the green flag is displayed. During a qualification session, a qualification attempt is halted.
WHITE FLAG: Displayed when the leader starts the final lap of the race. During qualifications, signals that driver has started final lap of qualification attempt.
ROYAL BLUE FLAG with DIAGONAL YELLOW STRIPE: The "passing flag," signals slower cars to yield to faster traffic.
RED FLAG: Signals that the race stops immediately, regardless of position of cars on the track.
BLACK FLAG: Directs a driver to proceed to the pits on the next lap and to consult with race officials.
BLACK FLAG with WHITE CROSS: Officials have ceased scoring the car until further notice.
ALTERNATING RED and YELLOW STRIPING: Signals that oil, water or some other substance has made track surface slippery.