Structural "Dynamics" is the study of how moving physical forces, such as wind, water, or even earthquakes, affect built structures. Offshore Structures can com-prise everything from oil and gas platforms anchored on sea bottoms, to marine or freshwater moorings, buoys, navigational systems, power and telephone lines, and even some built-up structures like floating heliports. Such structures often undergo stress from a variety of dynamic forces in combination, including waves, wind, and even seismic movements. Thus, the dynamics of offshore structures entails how these forces affect the planned or actual design of such structures and their expected behavior over time.