Field studies on the depth of folding, laboratory experiments in faulting with analysis of stress-strain relations, and the two-sided character of various mountain systems, have led to the conclusion that the wedge-shaped block is the typical form of compressed mountain ranges. The typical wedge apexes downward in the middle of the deformed zone. Other considerations have resulted in the extension of the wedge shape and wedge dynamics to plateaus and to the elevation and deformation of continents. This paper outlines the development of the theory, after which the folding of mountain chains, the elevation of plateaus and the deformation of continents are discussed briefly in terms of the wedge principle. Consideration is also given to the means of adjustment along the wedge borders, to the reasons for the asymmetry of mountain wedges, the importance of relative position on the continents and in the wedges in determining the direction of overfolding, and to certain aspects of the related vulcanism.