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Let’s provide some background information—BIM, or Building Information Modeling, is a digital tool used in engineering design, construction, and management. By creating digital models of buildings, it enables the sharing and transmission of information throughout the entire life cycle of a project, from planning to operation and maintenance. This allows engineering professionals to understand various building-related details accurately and respond effectively to them. It provides a foundation for collaborative work among design teams and all parties involved in the construction process, including owners and operators, and plays an important role in improving productivity, reducing costs, and shortening project timelines. Here, we cite the definition of BIM given by the U.S. **BIM standard (NBIMS); this definition consists of three parts: (1) BIM is a digital representation of the physical and functional characteristics of a facility (construction project) ； (2) BIM is a shared knowledge resource; it is a process for exchanging information related to a facility, providing a reliable basis for all decisions throughout its entire life cycle, from conception to demolition ； (3) At different stages of the facility, various stakeholders carry out collaborative work by inserting, extracting, updating, and modifying information in BIM to support and reflect their respective responsibilities. BIM has the following five characteristics: Visualization. Visualization means presenting things as they appear in reality. In the construction industry, the effective use of visualization is of great significance; for example, construction drawings typically show information about various components through lines, but the actual structure of those components has to be imagined by those working in the construction field. BIM provides a visual approach that allows people to transform traditional linear components into three-dimensional, tangible models that can be displayed before their eyes ； Now the construction industry also has design renderings. However, such renderings do not contain any information other than the size, position, and color of the components, and lack interactivity and feedback between different components. The visualization referred to in BIM is a type that enables interaction and feedback among various components. Since the entire process is visualized, the results can be presented through renderings and reports; more importantly, communication, discussions, and decision-making throughout the project’s design, construction, and operation phases take place within this visualized environment. Coordination is a key aspect in the construction industry; whether it’s the construction firms, the owners, or the design agencies, everyone is involved in coordination and cooperation. Once problems arise during the implementation of a project, it is necessary to bring together all relevant parties to hold coordination meetings in order to identify the causes of each construction issue and find solutions. Subsequently, changes are made and appropriate remedial actions are taken to resolve the problems. During the design process, various conflicts between different specialties often arise due to insufficient communication among designers from those specialties. For example, in fields such as HVAC, when arranging pipes, since the construction drawings are prepared separately for each component, during actual construction it is possible that structural elements such as beams exist in those areas and prevent the pipes from being installed there. Coordinating solutions to such collision issues can only be found after the problems arise. The coordination services of BIM can help address such issues; in other words, the BIM building information model can coordinate conflicts between different specialties during the early stages of building construction, generate coordination data, and make it available. Of course, the coordination function of BIM is not limited to resolving conflicts between different specialties; it can also handle issues such as the coordination between the layout of elevator shafts and other design elements as well as clearance requirements, the coordination between fire compartments and other design elements, and the coordination between underground drainage systems and other design elements. Simulability: Simulability allows not only the simulation of building models that have been designed, but also of things that cannot be operated in the real world. During the design phase, BIM can conduct simulation experiments for various aspects that need to be simulated in the design. For example: energy-saving simulation, emergency evacuation simulation, sunlight simulation, heat conduction simulation, etc ； 4D simulation (a 3D model combined with the project’s timeline) can be carried out during the bidding and construction phases; it involves simulating the actual construction process based on the organizational design for construction, thereby determining a reasonable construction plan to guide the work. At the same time, 5D simulation (based on a 4D model along with cost control) can also be carried out to achieve cost management ； During the later operation phase, it is possible to simulate the handling of daily emergencies, such as earthquake evacuation simulations and firefighter evacuation simulations. Optimality: In fact, the entire process of design, construction, and operation is one of continuous optimization. Of course, there is no essential inevitable connection between optimization and BIM, but better optimization can be achieved based on BIM. Optimization is constrained by three factors: information, complexity, and time. Without accurate information, it is not possible to achieve reasonable optimization results. BIM models provide information about the actual existence of a building, including geometric information, physical information, and regulatory information; they also offer information regarding the building’s state after it has undergone changes. When the complexity level is high, the capabilities of the participants themselves are insufficient to handle all the information; they must rely on certain scientific technologies and equipment for assistance. The complexity of modern buildings often exceeds the capabilities of those involved in their construction; BIM and various optimization tools associated with it make it possible to optimize such complex projects. The diagrammability of BIM models allows not only the creation of conventional architectural design drawings and drawings for component fabrication, but also enables visual representation, coordination, simulation, and optimization of buildings. It furthermore facilitates the generation of drawings specific to various specialties as well as detailed design drawings, thereby providing a more comprehensive representation of the project.