" Lett. 83, 1529 (1999) . S. F. Novaes, Standard Model: An Introduction, hep-ph:0001283 I. Models are usually man-constituted. That justifies talking about their purpose prior to talking about their consistency. Model Airplane Manufacturer Models are used as substitutes for originals because properties of the latter are of interest and the originals are not going to be investigated themselves. There may be a number of reasons for that such as taboos preventing from studying the original itself, or inability, the involved cost in terms of resources or moral damage being intolerable, or similar. "

" Black paint was also cheaper and more durable. Henry Ford is reputed to have made the statement "Any customer can have a car painted any color that he wants so long as it is black. " Model Ts in different colors were produced from 1908 to 1914, and then again from 1926 to 1927. By 1914, the assembly process for the Model T had been so streamlined it took only 93 minutes to assemble a car. That year Ford produced more cars than all other automakers combined. The Model T was a great commercial success, and for years in the late 1910s and early 1920s it was estimated that more than half of all motorcars in existence in the world were Model T Fords. In fact, it was so successful that Ford did not purchase any advertising between 1917 and 1923; in total, more than 15 million Model Ts were manufactured, more than any other model of automobile for almost a century. Model Airplane Airline This record has now been surpassed by the Volkswagen Beetle, and the Toyota Corolla and Ford F-Series nameplates have both sold more. The record is currently held by the Volkswagen Golf which sold over 21,000,000 units and is still in production today. "