EN
The scientific output of Marek Kuczma consists of 179 papers published in the years 1958-1993 and three books still used and quoted. Professor Marek Kuczma created and developed the theory of iterative functional equations but his name is also connected to important results on functional equations in several variables, in particular on Cauchy's equation and Jensen's inequality. In fact Marek Kuczma has founded a mathematical school: he supervised 13 Ph.D. dissertations, 10 his students have already their habilitation and 6 of them became full professors. The paper provides more information about the great teacher and some results of the outstanding mathematician.