CAD is mainly used for detailed engineering of 3D models and/or 2D drawings of physical components, but it is also used throughout the engineering process from conceptual design and layout of products, through strength and dynamic analysis of assemblies to definition of manufacturing methods of components. CAD is also extensively used in the design of tools and machinery used in the manufacturing of components, and in the drafting & design of all types of buildings, from small residential types to large commercial & industrial structures.