This is a VERY fun game to play -- especially when you install the 1.2.0.1 patch, provided by Papyrus right before they closed their doors for good -- until someone bought the source code and assets and made it to create the well-known sim known as iRacing. You can turn laps, go for a championship, or participate in "mock seasons", and play with two physics settings -- Arcade and Simulation. For the full experience, though, I would recommend the Simulation physics.
(Fun Fact: Two Sonic the Hedgehog voice actors provide the voices of your crew chief and spotter -- Jon St. John and Ryan Drummond, respectively)