What does it mean if you see one of these flags whilst at the race track? Some are entirely obvious but are there for the idiots where as some are unclear in our minds. The following chart gives indication as to what each flag means and when it should be used. Note that this is the European version of these flags. The American version of these flags is slightly different, especially with the white flag. If I were racing driver, I would prefer the European System. It is not hard to learn and is more informitive.

Flag Colour and Description
European Version	American Version
Green This should be used to indicate that the track is clear and should be waved at the observation post immediately after the incident that necessitated the use of one or more yellow flags. Green lights also indicate the start of the race and that the race may continue at full race speed.	Meaning is Identical
Blue Motionless - displayed to a driver to warn him that another competitior is nearby. Single waved - displayed to a slower driver to warn him there is a faster competitor coming up to lap him and that he should allow the car past. Double waved - displayed to a slower driver to let him know that a faster competitor is overtaking him.	The American System has one Yellow Stripe running diagonally down the flag from top right to bottom left. The conditions are pretty much the same. It is especially shown to lapped cars no matter what their pace is.
White This flag should be waved and is used to indicate to the driver that there is a much slower vehicle on the sector of track controlled by that flag point.	The white flag means the cars are on their final lap.
Black and White diagonal This flag should be shown once only and is a warning to the driver concerned that he has been reported for unsportsmanlike behaviour. This flag should be shown with a race number.	This flag is not used in American Motor Sport
Black This flag should be used to inform the driver concerned that he must stop at his pit or at the place designated in the supplementary or championship regulations on the next approach to the pit entry. If a driver fails to comply for any reason, this flag should not be shown for more than four consecutive laps.	The American Black flag is a combination of the European Black and White Diagonal, black flag and black with orange disk flags.
Black with Orange disc This flag should be used to inform the driver concerned that his car has mechanical problems likely to endanger himself or others and means that the he must stop at his pit on the next lap. When the mechanical problems have been rectified to the satisfaction of the chief scrutineer the car may rejoin the race. This flag should be shown with a race number.	This Flag is not used in American Motor Sport
Yellow Single waved - Reduce your speed, do not overtake and be prepared to change direction. There is a hazard beside or partly on the track. Double waved - Reduce your speed, do not overtake and be prepared to change direction or stop. There is a hazard wholly or partly blocking the track.	This flag is a combination of the European Yellow flag and the Red with Yellow stripes.
Red with Yellow stripes This should be shown motionless to inform drivers that there is a deterioration of adhesion due to oil or water on the track in the area beyond the flag.
Red This should be shown waved only on instruction from the Clerk of the Course when it becomes necessary to stop a practice session or the race. All drivers are required to slow down immediately and proceed to the pit lane (or the place foreseen by the regulations of the Event), and must be prepared to stop if necessary. Overtaking is not permitted.	All cars must come to a complete stop and turn off their engines. Overtaking is assumed to be not permitted.
Red and Yellow Diagonal This flag is not used in Australian Motor Sport.	All competitors must return to their original grid positions for a race restart, unless they have had some sort of penalty.
Black and White chequered This flag should be waved and signifies the end of a practice session or the race.	Meaning is identical.