Historically, architects, engineers, and designers prepared their drawings by hand, using the equipment shown here. This required an extensive collection of specialized tools and instruments, large drawing tables, printing devices, and file storage. Substantial training and practice was needed to become proficient in the principles of mechanical drawing. The invention of Computer Aided Design (CAD) eliminated the need to hand-draw projects anymore. CAD provided the drafter with all the necessary tools at their fingertips. A PC keyboard, mouse and monitor is all you need. CAD improves productivity, accuracy, and consistency, making it far more efficient the manual drafting. Changes can be executed quickly and accurately with precision within the application.