The document defines and provides examples of different types of bridges and structures. Suspension bridges are lightweight and can span long distances with cables supported by tall towers. Arch bridges can support heavy loads by transferring weight through dynamic forces along an arch shape. Beam bridges can be short or long with added piers and are designed for frequent use. Truss bridges are also lightweight and strong through triangular beam frameworks. Shell structures are strong and protective of interiors, like an eggshell. Frame structures gain strength from their connected parts, like a spider web or snowshoes. Solid structures strongly support themselves against weathering but are difficult to move due to mass, like a canyon or apple.