Sezgin Koçak

Fixed cost:
Fixed costs are those that are incurred in a predetermined amount, regardless of how many units of the product are manufactured. Purchasing the injection mold required for the new intake manifold is an example of fixed cost. Whether 1000 or 1 million units are produced, the fixed cost of the mold is incurred and does not change. Another example ist the cost of setting up the factory work area for the intake manifold assembly line. This cost is also fixed, regardless of how many units are produced.Despite the terminology, however, no cost s trully fixed. If we quadruple the production quantity, we may have to build anther production line. When considering a cost as fixed, ranges of production quantities and the assumed time horizon should be specified.
(K.T. Ulrich, S.D. Eppinger, Product design and development,4th edition, p. 215)

Variable cost:
Variable costs are those incurred in direct proportion to the number of units produced. For example, the cost of raw materials is directly proportional to how many intake manifolds are produced, and therefore to how many 3.8-liter V6 engines are made. Assembly labor is sometimes considered a variable cost as well because many firms can adjust the staffing of assmebly operations by shifting workers to other areas on short notice.
(K.T. Ulrich, S.D. Eppinger, Product design and development, 4th edition, p. 215)

Group Technology:
Group technology (GT) is a concept that seeks to take advantage of the design and processing similarities among the parts to be produced. Because many parts in products have certain similarities in their shape and in their method of manufacture. The similarity in the characteristics of similar parts suggests that benefits can be optained by classifying and coding these parts into families. By disassembling each product into its individual components and then identifying the similar parts, one company found that 90% of the 3000 parts made by company fell into five major families of parts.
(Kalpakjian S., Schmid S.R.,Manufacturing engineering and technology, 5th edition, p. 1208)

Reverse Engineering:
Reverse engineering is the process extracting the knowledge or design blue-prints anything man-made. The concept has been round since before computers or modern technology, and probably dates back to the days of the industrial revolution.
(Reversing: Secrets of reverse engineering, p. 3)