This section of the book talks about how the construction of buildings and architecture aren’t really the same but it is useful to know how the different parts of the building come together so that it can be successful, specifically the physical systems. These systems define, organize, and reinforce the ordering of a building. For example, three types of systems are structural, enclosure, and mechanical. Structural systems is about the building being designed and constructed so that people can access it. The enclosure system is the outside of the building like the roof, exterior walls, windows, and doors. Lastly, the mechanical system is the services that can be provided to a building, like heating and ventilation or the water supply. These three systems all come together even though they deal with different parts.