Test-worthy bridge.

In terms of structure and material, what makes a bridge strong?
Are some shapes (truss, suspension, beam, cable stay, etc) and/or materials better than others? If so what are the pros and cons of working in different construction methods or different materials?
Is one type of bonding (gluing), joining methods or patterns, or fastening stronger than another? Explain.
What are the typical structural components of several different bridge designs?
What types of beams, cables, fasteners are used?
How do the forces that are applied in tension, compression, or torque effect your design?
Does the shape of the final design have any effects on strength? Why?
What are the purposes of a bridge? (why do people make bridges instead of doing something else? i.e. ferry, cars that can float, etc.)
What makes for a good bridge? (What are an engineer’s goals for constructing bridge? i.e. symmetry, width, cost, etc.)
Everything else you need to know to maximize you bridge design