In modern CNC systems, end-to-end component design is highly automated using computer-aided design (CAD) and computer-aided manufacturing (CAM) programs. These programs produce a computer file that is interpreted to extract the commands needed to operate a particular machine via a postprocessor, and then loaded into the CNC machines for production. Since any particular component might require the use of a number of different tools-drills, saws, etc., multiple tools are combined into a single "cell". In other cases, more than one machine is used. In either case, the complex series of steps needed to produce any part is highly automated and produces a part that closely matches the original CAD design.