Prototypes

Prototypes or prototypical instances combine the most representative attributes of a category. They are the best examples among the members of a category and serve as benchmarks against which the surrounding "poorer" instances are categorized (see Prototype (linguistics)).

See also: Categorization, Semantics

Computer science

In computer science, a function prototype is the declaration of a function or subroutine. However, in prototype-based programming (in the context of object-oriented programming), a prototype is an object that can be cloned in order to produce new objects.

Model railroads

Among model railroad enthusiasts, at least in North America, actual railroads are commonly spoken of as "prototypes".

Scale Modeling In General

In the field of scale modeling (which includes model railroading, vehicle modeling, airplane modeling, military modeling, etc.), a prototype is the real-world basis or source for a scale model - such as the real EMD GP38-2 locomotive, which is the prototype of Athearn's (among other manufacturers) locomotive model. Technically, any non-living object can serve as a prototype for a model, including structures, equipment and appliances, natural wonders (like trees), and so on, but generally prototypes have come to mean full-size real-world vehicles including automobiles (the prototype 1957 Chevy has spawned many models), military equipment (like M4 Shermans, a favorite among US Military modelers), railroad equipment, motor trucks, motorcycles, airplanes, and space-ships (real-world like Apollo/Saturn Vs, or the ISS). There is debate whether 'fictional' items can be considered prototypes (like Star Wars or Star Trek starships, since the feature ships themselves are actually models or CGI-artifacts); however humans and other living items are never called prototypes, even when they are the basis for models and dolls (especially - action figures).

Automobile racing

Cars from the premier tier of international sports car racing are informally called 'Prototypes'. Unlike GT cars, which are road-legal cars modified for racing, Prototypes are designed purely for track use. The overall winners of multi-class events like Le Mans are usually Prototypes. Examples of Prototypes include the Porsche 917 and Audi R8.