Computer-Aided Design
Computer-aided design (CAD) is the use of computer systems (or workstations) to aid in the creation, modification, analysis, or optimization of a design. CAD software is used to increase the productivity of the designer, improve the quality of design, improve communications through documentation, and to create a database for manufacturing. CAD output is often in the form of electronic files for print, machining, or other manufacturing operations. The term CADD (for Computer Aided Design and Drafting) is also used.
Computer-Aided Engineering
Computer-aided engineering (CAE) is the broad usage of computer software to aid in engineering analysis tasks. It includes finite element analysis (FEA), computational fluid dynamics (CFD), multibody dynamics (MBD), durability and optimization.
Design
Design is the creation of a plan or convention for the construction of an object, system or measurable human interaction (as in architectural blueprints, engineering drawings, business processes, circuit diagrams, and sewing patterns). Design has different connotations in different fields (see design disciplines below). In some cases, the direct construction of an object (as in pottery, engineering, management, coding, and graphic design) is also considered to use design thinking.
Engineering
Engineering is the creative application of science, mathematical methods, and empirical evidence to the innovation, design, construction, operation and maintenance of structures, machines, materials, devices, systems, processes, and organizations. The discipline of engineering encompasses a broad range of more specialized fields of engineering, each with a more specific emphasis on particular areas of applied mathematics, applied science, and types of application. See glossary of engineering.
Design
From a structural point of view, design is totally useless... I tried to give my products a little sense and energy. But even when I gave the best of myself, it was absurd.
Philippe Starck (2008) in: "Les doutes existentiels de Philippe Starck", Marie-Douce Albert, Le Figaro, March 28, 2008, p. 32
Engineering
Engineering is the conscious application of science to the problem of economic production.
Halbert Powers Gillette (1910). cited in: T.J. Hoover & J.C. Lounsbury Fish. The Engineering Profession. Stanford University Press, 1941. p. 463
Design
This is exactly the meaning of design: the conflict between form and content, form being the problem. [...] It is the coming together of form and content that is the realization of design.
Paul Rand (2008), Conversations with Students p. 32