This paper presents a well-balanced and nicely written overview of the theory of computation, with special emphasis on the role that mathematicians have played in the last century. The main characters are Claude Shannon, Kurt Gödel, Alan Turing, Alonzo Church, Stephen Kleene, John von Neumann, Michael O. Rabin and Dana S. Scott, Stephen A. Cook, Leonid Levin, John Backus, Donald Knuth. The level of the exposition is elementary, but important concepts and ideas are appropriately highlighted.