Fundamental relations are derived for a single elementary process by using concepts of "generalized time" and "generalized rate". These concepts are useful for describing reactions in which only a single elementary process is involved, and by using these useful relations iso-conversion methods for kinetic analysis, both of integral methods and a derivative method, are derived and explained with some illustrations. The methods for kinetic analysis and other descriptions in this article are also applicable to physical changes of a single elementary process, such as diffusion and thermal stimulated currents.