The regulations

Flags

Green flag

Start of practice, qualifying or race. Also used for race restart after caution (yellow flag) and red flag periods.

Yellow flag

Caution. Drivers must slow down, no overtaking allowed. Also signals the presence of the safety car on the race track.

Blue flag

A faster competitor is about to overtake.

Yellow flag with red stripes

Signals the presence of oil or water on the race track.

White flag

You are catching up with a much slower vehicle.

Red flag

Immediate race stop, cars must come back to the pits at slow pace. No overtaking allowed.

Black flag

Last warning before exclusion from the race for non sporting driving.

Black flag with yellow disk

Notifies a driver to leave the race track immediately because of a mechanical problem he is unaware of (a leak for example). Must be shown with the car’s race number.

Checkered flag

End of practice, qualifying or race.