Watching the NASCAR Flagman

After all NASCAR's inspections are passed, cars are ready to get out on the track. From that point on, keep your eye on the flagman, who is perched above the racetrack at the start/finish line in a crow's nest of sorts. You can't miss him — he's the guy waving all those flags.

What do all those flags mean? Here's the lowdown:

Green: To keep things simple, green means go. The flagman waves the green flag to signal the start of the race. During a few pace laps, which are run at a slower pace so that cars can warm up their engines and tires, a pace car with lights on its roof leads the field.

Just before the race starts, though, the pace car peels off onto pit road as the flagman waves the green flag. Then, they're off!

Yellow: The yellow flag, or caution flag, comes out when drivers need to slow down because the track is unsafe. This happens in the event of an accident, rain, or when debris or oil is on the track. When the yellow flag is waved, drivers can't race or pass each other. The position of each car in the field is frozen at the moment when the yellow flag flew. Until late 2003, drivers were allowed to race back to the yellow because the caution period didn't formally begin until the leader crossed the start-finish line. Often, a driver with a big lead would slow his car on the way to the line to allow lapped cars to make up a lap. To compensate for the elimination of this tactic, NASCAR instituted a new rule that allows the first car one lap down to pass the pace car and make up his lost lap. This rule immediately became known as the "Lucky Dog Rule."

Some fans don't appreciate paying to attend a NASCAR race, only to see it end under a caution flag — which is completely understandable. Drivers don't always feel the same way when a caution comes out. Sometimes, they are happy about it because they need a pit stop for gas or fresh tires, or because the car in the lead is a mile ahead of everyone and cars are bunched back up for a restart after a caution, bringing everyone closer to the leader. Sometimes, though, a driver hates to see a caution flag, especially when he's leading by a mile or when his car drives better after long runs at full speed.

Green-White-Checkered Sequence: In an attempt to finish races under green-flag conditions, NASCAR in 2004 introduced the green-white-checkered flag sequence. This is used when a yellow flag flies with just a few laps remaining and the race would otherwise have finished under caution. The new procedure consists of a restart of two laps — the green flag for the first lap of the restart and the white flag signaling the final lap leading to the checkered flag. Used only during the last two scheduled laps of a race, the new format does not guarantee a green-flag finish, as only one restart under the green-white-checkered format will be attempted. If a caution comes out during that period, the race is finished. This procedure eliminates the need for a red flag in the final laps to immediately stop the race in an attempt to finish under green-flag conditions. One offshoot of the new rule is that crew chiefs have to recalculate gas mileage, as under regular racing conditions most cars have the exact amount of fuel needed to finish the race as regularly scheduled. With events possibly being extended by two laps, a crew chief has to decide whether to stop late in the race for a splash of gas or gamble that it will finish on the designated lap.

Red: When a red flag waves, cars must stop wherever they are on the track. The pace car then comes out and slowly leads them to a safe place designated by NASCAR. If drivers are on a part of the track where they can't see the red flag, their crew chief gets on the two-way, in-car radio and tells them to stop.

A red flag comes out when a dangerous situation exists on the track — like a lot of oil or fluid covering the surface or a damaged wall or fence — and it would be unsafe or impossible for cars to continue to circle the track under caution. Also, if it is raining so much that drivers can't see the track (or if the track is too wet and slippery), the red flag stops the race until the conditions improve.

Depending on how long a race is under the red flag, drivers may sit in their cars, get out and talk with one another, or — during a long rain delay — head for their trailers parked in the infield.

Black: A black flag signals to the driver that he must get off the track and go to his pits. This happens when something is wrong with his car, such as oil leaking or smoke billowing from the exhaust, which may create a dangerous situation for other cars on the track. The black flag can also come out when a driver breaks the rules, like when he jumps the start.

When a driver is black-flagged, he knows it. Not only does the flagman wave that ominous, dark flag at him, but his car number also is displayed at the start/finish line so drivers know exactly who's in trouble. A driver can't really ignore getting black flagged, either, and just stay out on the track to race.

At some point, officials get peeved and the flagman breaks out a black flag with a white "X" on it, indicating the driver won't be scored any longer. In that case, a driver should give up and head to the pits.

Blue with diagonal yellow stripe: When a driver sees this flag, it signifies that faster, lead-lap cars are about to pass him and he must yield to those cars. A flagman usually waves this flag at a driver who is one lap down and is significantly slower than the cars racing for the win.