A concept car is a car prototype made to showcase a new vehicle's styling, technology, and overall design before production. They are often shown at motor shows to gauge customer reaction to new and radical designs which may or may not have a chance of being produced.
General Motors is generally credited with inventing the concept, or show, car, and definitely did much to popularize it through its traveling Motorama shows of the 1950s.
Concept cars rarely go into production directly; most undergo at least some changes before the design is finalized for the sake of practicality and cost. Concept cars are often radical in design. Some use non-traditional, exotic, or expensive materials, ranging from paper to carbon fiber to exotic alloys. Others have unique layouts, such as gullwing doors, 3 or 6 (or more) wheels, or special abilities not usually found on cars.
Because of these often impractical or unprofitable leanings, many concept cars never get past scale models, or even drawings. Other more traditional concepts can be developed into fully driveable vehicles with a working drivetrain and accessories. The state of most concept cars lies somewhere in between and usually does not represent the final product.
If driveable, the drivetrain is often borrowed from another production vehicle from the same company, or may have defects and imperfections in design. They can also be quite refined, such as General Motors' Cadillac Sixteen Concept  (http://www.cardesignnews.com/autoshows/2003/detroit/highlights/h06-cadillac-sixteen.html).
Inoperative "mock-ups" are usually made of wax, clay, metal, fiberglass, plastic or a combination thereof.
After a concept car's useful life is over the cars are ususally destroyed. Some survive, however, either in a company's museum or hidden away in storage. One unused but operational concept car that languished for years in the North Hollywood, California shop of car customizer George Barris, Ford Motor Company's "Lincoln Futura" from 1954, received a new lease on life as the Batmobile in the Batman series that debuted in 1966 on the ABC Television Network.
Some concept cars
- Buick "Y" Job" - Designed in the late 1930's by the famous General Motors designer Harley Earl. picture at "http://www.classicar.com/harley_earl3.asp". This is considered by most to be the first concept car.
- 1956 General Motors Firebird - a Gas Turbine four seater with a plastic "Bubble Top" roof. Three versions shown at "http://www.carofthecentury.com/"
- Buick LeSabre - Picture at "http://info.detnews.com/history/story/index.cfm?id=101&category=people"
- Bugatti Rinspeed EB110 Cyan - A Bugatti EB110 tuned by the Swiss company Rinspeed
- BMW Z9 Concept - Many people consider the BMW 6-Series the production version of this coupé concept (http://www.autointell-news.com/european_companies/BMW/bmw-z9-coupe-01.htm).
- Ford MA concept car A stunning wedge shaped two seater with a bamboo body
- Ford Mustang GT - This concept is slated to replace the current Mustang in 2005  (http://www.cardesignnews.com/autoshows/2003/detroit/highlights/h08-ford-mustang.html)
- General Motors Ultralite a 1992 4 door 4 passenger 88 mpg ultra light
- Opel Frogster - The green prototype of 2002
- Volvo YCC a car for ladies
- Toyota Sportivo Coupe - The Sportivo Coupe is a concept car that demonstrates new styling, interior dynamics, and a high technology approach to road safety. - Pictures at "http://www.mybarina.com/gallery/Toyota-Sportivo-Coupe"