The study of sea waves has always been in the focus of mankind's atten­ tion. This is attributed not only to a desire to understand the behaviour in seas and oceans, but also, it has some practical necessity. Developing up-to­ date wind wave numerical methods requires detailed mathematical modelling, starting with wave generation, development, propagation and transformation on the surface in different water areas under quasi-stationary conditions, up to a synthesis of climatic features observed under different wave generation conditions in oceans, sea or coastal areas. The present monograph considers wind waves in terms of the most general formulation of the problem as a probable hydrodynamic process with wide spatial variability. It ranges between the global scale of the oceans, whose typical size is comparable with the Earth's radius, to the regional and local scales of the seas, including water areas limited in space with significant current or depth gradients in coastal zones, where waves cease their existence having propagated tens of thousand miles.