Green - Green means go! This flag could signal the beginning of the race or a restart after a caution.
Yellow - Caution is out. Drivers need to slow down due to unsafe conditions on the track. Cautions may be brought out because of an accident, rain or debris on the track.
Red - Red means stop. Cars must stop where they are. There is danger on the track that makes it unsafe for cars to proceed around the track, even under a yellow flag.
Black - This flag signals to a driver that he must get off the track and go to his pit. This occurs if there is something wrong with the car such as leaking oil, smoking or something wrong with the car that could be a danger to the other drivers on the track. It could also mean the driver broke a rule and is going to be penalized by NASCAR.
Blue Flag with Diagonal Yellow Stripe - This flag signals to a slower driver (usually a lap down) to move over and let a faster driver on the lead lap to pass.
White - This flag signals the lead car that he has one lap to go.
Checkered - Finish! When the checkered flag waves
it means the winner has crossed the finish line and won the race. Also known
as taking
the checkered flag.
Some drivers take the checkered flag and do a victory lap around the track
with the flag displayed to share the victory with the fans.