The Standard Model obeys Poincaré symmetry, whose generators are the spacetime translations P and the Lorentz transformations J μν. In addition to these generators, supersymmetry in (3+1)-dimensions includes additional generators Q α, called supercharges, which themselves transform as Weyl fermions. The symmetry group generated by all these generators is known as the super-Poincaré group. In general there can be more than one set of supersymmetry generators, Q α, I = 1,..., N, which generate the corresponding N = 1 supersymmetry, N = 2 supersymmetry, and so on. Supersymmetry can also be constructed in other dimensions, most notably in (1+1) dimensions for its application in superstring theory.