Track limits

Full drawn white line
The limit of the track, when there are no kerbs.

Normal kerbs (Rumble strips)
These kerbs will produce a rumbling sound when driving over them, they will not particularly slow down the car.

Sausage kerbs
These kerbs are like small ramps that has the aim of discourage drivers to cut corners or going too wide as they will slow down and can damage the car.

Definition of being on track
Minimum 2 wheels always on track, kerbs count as track. Some tracks have places where this differs a bit.

Leaving track
This will invalidate the lap time. So the sim wont show you your time, and the time wont count in Qualifying session. However it wont affect your position in a race.

In multiplayer you will also receive Incident points for leaving track.