Truck Racer does exactly what its title suggests: There are trucks, and you race them. Generic title aside, Truck Racer is a fairly good arcade-oriented big rig racing game that is held back by a lack of difficulty and empty multiplayer lobbies. If you must buy it, wait for a sale.
Truck Racer follows the standard racing game blueprint: you race transport trucks through a series of increasingly difficult tournaments, trying to earn enough credits to unlock the next tournament. Credits earned can be used to purchase new trucks and unlock better performance parts. There are six trucks to choose from and quite a few different parts to unlock, and it's fun mixing and matching components to get the best possible performance out of your vehicles.
The racing in Truck Racer is decent, with good course design and responsive controls. There's lots of banging and crashing as the trucks battle for position; expect to see lots of pileups and parts littering the tracks. Trucks can get damaged, but damage doesn't seem to affect handling. It's possible for trucks to take enough damage to render them useless, but don't expect it to happen even once over the course of the eight or so hours it takes to complete Truck Racer's career mode.
Since it's an arcade-oriented racer, the physics in Truck Racer are a bit more relaxed. The trucks drift fairly easily, and crashes that should flip the truck never will. This keeps the action moving along, although somewhat curiously Truck Racer doesn't have a "reset to track" feature, which means if your truck spins out and you're facing in the wrong direction, you'll have to slowly back up and get back on the track manually.
Truck Racer's biggest problem is its level of difficulty. This is an easy racing game. You'll finish atop the podium in every race the first time you race it. Part of this is due to the game's AI: computer-controlled racers are kind of dumb, and they have real problems getting unstuck from accidents. While the other trucks are trying to get going again after a pileup, you'll leave them in the dust and the lack of rubber-banding means the other trucks will never catch up to you. Expect to win many races by more than 30 seconds. Even on Expert difficulty, Truck Racer is a breeze.
Live competition would cancel out the bad AI in Truck Racer's single-player mode, but no one is playing this game online. This means Truck Racer has a short shelf life, unless you know some people who have the game and will play multiplayer.
Steam achievements add some extra replay value, for people who are into that sort of thing. There are fifty in all, with most of them obtainable in career mode.
Truck Racer is a decent racing game, with the added novelty of being one of the few titles out there that only feature trucks. It's a good game to pick up in a sale.