Substructure refers to the underlying framework or foundation that supports a larger structure. In construction, it includes elements like foundations, basements, and footings that provide stability and strength to buildings. A well-designed substructure is crucial for ensuring the safety and durability of the entire structure above it. In engineering, substructure can also apply to the underlying components of systems, such as software or networks. These foundational elements enable the higher-level functions to operate effectively. Understanding substructure is essential for architects, engineers, and designers to create reliable and efficient systems.