The relations between congruences andgreen equivalences in semigroups

In this study, semigroups, homomorfizm, congruences, Green equivalence relations, Completely regular semigroups were given. We explain the concept of kernel congruences, trace, congruence pairs, normality and left m-normal of congruences that has an important role in semigroups. To study congruence's kernel and trace easier is than directly to study about congruences. The kernel of homomorfism is a congruence. Moreover the relations between congruences and Green equivalence relations were given.