The 24 Hours of Le Mans is one of the oldest car race in endurance racing, starting in 1923, it is still considered as one of the most popular and hardest race in the world. It is hard for the cars and for the drivers because all cars must be able to race 24 hours without any mechanical malfunction.
This is also very hard for the manufacturers, because many parts (brakes, tires and etc.) are normally replaced after just one race, but here those parts must function 24 hours. Drivers have a tough challenge also because they are driving 2 hours, then they hand duties to another driver and have 4 hours to eat and rest (because there are three drivers per car).
In the beginning, cars were the same as those sold to the public, but during the time they developed, and today they are completely different than cars you can actually buy. There are two classes: two-seat Prototype (enclosed-bodywork) sports cars and two classes of GT (Grand Turing) cars, which have some resemblance to cars sold to the population.
The regulations say that all cars must have two seats (in the last year only place for the second seat was needed), two doors, and a roof (in previous years roof wasn’t required, but because safety concern it is obligatory now).
On the 13-14 June, 2015, 83rd race at Le Mans will be held. Automatic invitation will have teams that won in the previous year their class. They can change the car, but changing the class is forbidden. In the last 5 years, Audi is the winner of this race.