Wind turbines are designed and analyzed using simulation tools capable of predicting the coupled dynamic loads and responses of the system. In this paper, an overview of the capabilities of a Computer-Aided Engineering (CAE) tool called FAST or Fatigue, Aerodynamic, Structures, and Turbulence in modeling wind turbines in different depths of water will be presented. Different offshore wind turbine support systems structures will be discussed. These support systems are classified into three categories according to the water depth, namely, shallow water, translational water and deep water depths. This paper will be focusing on the support structures used in translational and deep water depths only. This will also be focusing on incorporating hydrodynamic loading for multimember structures using FAST through its hydrodynamic loading module, Hydrodyn. Also, a quantitative comparison of th*e responses of different floating platforms will be tackled.