We think that to progress in the mechanism of regular and breaking wave propagation, it is necessary to realize more physical studies from which only coherent theories can be established. This method is applied in the paper. We explain in this way the physical meaning of the regular wave propagation but also the complex mechanism of their breaking shape even over an horizontal or inclined bottom. We present interesting results concerning breaking wave sollicitations on vertical breakwaters and we compare their free surface shapes with the corresponding profiles obtained in our laboratory. We propose here a fundamental study which is defining important computation possibilities of complex phenomena like the regular and breaking wave action on fixed structures.