Differential equations aspects of quantum cohomology

The quantum differential equations can be regarded as examples of equations with certain universal properties which are of wider interest beyond quantum cohomology itself. We present this point of view as part of a framework which accommodates the KdV equation and other well known integrable systems. In the case of quantum cohomology, the theory is remarkably effective in packaging geometric information; we illustrate this with reference to simple examples of Gromov-Witten invariants, variations of Hodge structure, the Reconstruction Theorem, and the Crepant Resolution Conjecture. Based on lectures given at the summer school "Geometric and Topological Methods for Quantum Field Theory", Villa de Leyva, 2007.