Intergraph Smart®, 3D - a next-generation, data-centric, rule driven solution - was specifically designed to meet mission-critical requirements. It breaks down the barriers of traditional technologies to allow for an iterative engineering design environment. Smart 3D offers all the capabilities necessary to design plant, marine, and materials handling facilities. It also allows for maintenance of their 3D "as built" representations, which gives businesses a competitive advantage. 3D Computer-Aided Design software (CAD) assists in creating, modifying and optimising a design. Hexagon PPM provides the best CAD software for companies that design, construct and operate industrial facilities. 3D CAD is used primarily for detailed engineering, but it can also be used throughout the entire engineering process, from conceptual design to maintenance and operation. Design and visualisation play a significant role in the representation of physical assets in the digital twin concept.