A formation lap is a lap completed before starting the race. Formation lap is also known as test lap and parade lab. In the formation lap, the drivers finish the lap slowly. This lap allows drivers to get used to the track and identifies critical areas on the track.
Another purpose of the formation lap is to keep the tires warm since tire blankets are not as efficient as running on the track. This gives drivers a better grip to handle the car. Warm-up laps show if the car is in fact in tip-top condition.