Testing is done alone, with no official scoring of times. Laps are timed within the simulation, but the results of testing are unofficial and are not saved or published to the website as other results are. Incidents do not count against you in testing. You can test any track and car you've purchased by pressing the TEST button on the navigation bar, or you can test the current series car and track for the race week by pressing the TEST CAR ON TRACK button from the race panel. Testing is not an official session. You can test whenever you like for as long as you like.
Practice sessions are unstructured practice time. Official lap times are recorded, but incidents do not affect your Safety Rating or License. Practice sessions are generally 30 minutes in length.
Qualifying sessions determine the overall weekly qualifying order, which is used to grid cars in race sessions. You may qualify as few or as many times as you like during the week. The order is updated throughout the week, and race sessions are gridded according to the qualifying order as it exists at the session start time. You do not need to have a qualifying time in order to race. In that case, you will be gridded toward the back of the field, with your position among other non-qualifiers based on your iRating (see below). Road Race qualifying sessions are generally 30 minutes in length with multiple drivers on the track at any time. Ovals feature single-car qualifying sessions — no other cars are on the track with you — and your qualifying time is generally the best of 4 laps.
A Time Trial is a competition between you and the clock (and everyone else and the clock!) You are on track alone and must try to record the fastest sequence of laps without spinning, going off the track, or having contact with a barrier. Any such incident will invalidate your current lap sequence, and you will need to complete another full sequence in order to better your time. The Time Trial time is your average lap time for your best sequence of laps in the session. The number of laps in a full sequence varies from track to track, or from configuration to configuration.
These are the real deal. You are racing against a field of other drivers in real-time. Standing starts are used for road races, and rolling starts are used for oval races. You may start moving when the red lights turn green for road courses and once the pace car rolls for ovals. Remember the old adages that races are not won in the first turn or on the first lap, and that to finish first, first you must finish.
Once the simulation launches, you can drive in a five-minute warm-up session. Upon completion of that warm-up, the checkered flag will be displayed and a cool-down period will begin. The cool-down varies from track to track and is based on the average lap time for that track. During the cool-down period, if you exit your car, the RACE button will be grey and you cannot reenter the track until the field is being put on the starting grid. Once your DRIVE button turns green you have 60 seconds to grid your car by pressing the RACE button. Once all cars are on the grid, the lights turn red and the start is only seconds away.