The fourth edition of the textbook provides information on various aspects and types of computer-aided design systems required by qualified CAD users in various fields of technology. Significant attention is paid to the mathematical support of the procedures for the analysis and synthesis of design solutions used at various stages of design. The composition and functions of CAD technical support, methods of conceptual design of complex systems, technology of information support of products (CALS-technologies), as well as issues of CAD integration with automated control systems in industry are considered. The content of the textbook corresponds to a course of lectures that a talented author gives at MSTU named after N.E. Bauman. For students of higher technical educational institutions. It can be useful for graduate students and industry workers who use CAD methods and tools in their work.