Let $K$ be an algebraically closed field of characteristic $0$ and $G$ a finite group. I know that the group ring $K[G]$ is a semisimple and so decomposes as a direct sum of $m$ simple components where $m$ is equal to the number of irreducible characters of $G$.
What is the exact relationship between these Wedderburn components and the (complete) set of irreducible characters? In particular how does this relate to the contragredient character of an irreducible character?
Many thanks for your help.