Concordance is a relation which classifies knots in 3-space via surfaces in 4-space, and it is closely related with low dimensional topology. Satellite operators are one of the main tools in the study of knot concordance, and it has been widely used to reveal new structures of knot concordance. In this talk, I will explain interplay between concordance and low dimensional topology, and discuss recent developments on satellite operators. The talk is based on joint work with Jae Choon Cha.