All the colors are used to give a signal to all the participants in the sport. The flags should be of cloth, lights or of coded boards.
It means the track is clear and the sport can be commenced or can be resumed. Sometimes even the national flag of the host can also be displayed instead of green.
It means that there may be some blockage in the race course and the racer may be racing in extreme caution and may even slow down a bit or be prepared to change the directions. Overtaking during this time is strictly forbidden.
This sign is used when the race is stopped. During this time, the competitors are not supposed to overtake and are advised to stop immediately with caution.
Diagonal red lines on white indicates that the competitor is either at the start or at the finish line of the race course.
Black and white checker flag indicates the completion of the race.