Understanding how chemical reactors work lies at the heart of almost every chemical processing operation. Basis information for modeling and simulation of chemical reactors is needed from mass transfer, heat transfer and chemical kinetics. Only simple problems from practice can be solved analytically by means of integration of the differential equations. POLYMATH is a extremely user-friendly software package which makes modeling easy for the education of chemical engineers and chemists. POLYMATH is used to numerically solve coupled differential equations simultaneously or to find kinetic parameters in rate expressions by regression. Using an identified model the influence of various reaction parameters on the overall process can be simulated easily.