Inconsistency of geoid definition as a physically meaningful level surface is emphasized; it is affirmed that any level surface, intersecting the physical earth surface, can be considered as a generalized earth surface – geoid. The generalized formula for orthometric and normal heights is proposed, unifying the formulas for geodetic height, both in Stokes' and in Molodensky's theory. The advantages of normal height, its connections to different measurable quantities are pointed out. The physical essence of the concept of quasigeoidal height and the role of quasigeoid surface are revealed.