  We use the computational power of rational homotopy theory to provide an
explicit cochain model for the loop product and the string bracket of a
1-connected closed manifold M. We prove that the loop homology of M is
isomorphic to the Hochschild cohomology of the commutative graded algebra
A_{PL}(M) with coefficients in itself. Some explicit computations of the loop
product and the string bracket are given.
