For the careless viewer, there can be a great deal of confusion when it comes to classifying closed-wheel racing cars as the 'touring cars' or the 'sports cars' (as well known as GT cars). In fact, there is often extraordinarily little technical difference between the two classifications, and nomenclature is often a matter of tradition.
Generally, on the other hand, touring cars are based upon 4-door 'family' sedans or, more rarely, 2-door coupe cars, while GT racing cars are based upon more striking vehicles, like Ferrari's or Lamborghini's. Underneath the bodywork, a Touring Car is sometimes more directly associated to its road-going origins, using numerous original components and mountings, while a top-flight GT car is often a purpose-built tube-frame racing chassis underneath a decorative body shell. Numerous Touring Car series, like the BTCC and the now-defunct JTCC differentiate themselves from sports-car racing by featuring front-wheel drive cars with less important engines.
On the other hand, while generally Touring Cars have a lower technical level than sports cars; there are famous exceptions to the rule. The Deutsche Tourenwagen Masters (DTM) is believed to be one of the most technologically highly developed racing series in the world, with cars that, underneath their four-door shells, are more purebred racing machines than the majority FIA-GT vehicles.