Book excerpt: Computer aided design (CAD) is the rendering of architectural drawings using the computer, which today plays a central role in almost all architectural firms. This volume explains the principles and fundamentals of CAD and provides the student with a simple and easily understandable path to using the computer as a tool and medium. Subjects: The architectural design in dialogue with the computer; An introduction to working with software and hardware; Practical, user-oriented explanations of CAD functions; Digital visualization; Interfaces and data processing.