Substructures are the underlying components or systems that support a larger structure. In construction, for example, the substructure includes elements like foundations, basements, and footings, which provide stability and strength to buildings. These components are crucial for ensuring that the entire structure can withstand various loads and environmental conditions. In a broader context, substructures can also refer to the foundational elements of any system, such as the social structures that support a community or the economic frameworks that underpin a market. Understanding these substructures helps in analyzing how larger systems function and interact with one another.