This review is an elementary introduction to supersymmetry. The example of supersymmetric quantum mechanics is used to discuss the basic concepts of supersymmetry and its characteristic features: anticommuting variables, supercharges, the cancellation of divergences, the vanishing of the vacuum energy, the degeneracy of energy spectra, and the spontaneous breaking of supersymmetry. The form taken by supersymmetry in problems in quantum mechanics and nuclear physics is discussed. The use of a supersymmetric formalism in statistical physics and field theory is also discussed.