Process planning in manufacturing involves defining the operations required to transform a product or a component part from a rough to a finished state in accordance with the specifications cited on a manufacturing drawing. Manufacturability is the ability of a product to be manufactured in a cost-effective manner. Contemporary techniques, such as computer-aided design (CAD), computer-aided process planning (CAPP), and rapid prototyping, have helped to shorten lead time. The methods and processes involved in preproduction planning are varied, depending on the type of manufacturing industry involved, complexity of the product, anticipated volume of production, and expected duration of production. A process plan summarizes and provides a record of the sequence of events required to manufacture, assemble, and/or process a product. The choice of a method or process for machining a part largely determines the type of machine tool needed. Once the decision on the type of machine for an operation has been narrowed to one size of two or more kinds of machines, it then becomes necessary to estimate and compare the costs.