Histra uses an innovative Discrete Macro-Element (DMEM) approach which guarantees an extremely high degree of accuracy in the response, comparable with other advanced FEM modeling approaches and with a low computational burden. In fact, the degrees of freedom of the model are not proportional to the number of nodes, but to the number of macro-elements into which the structure is discretized. Each Macro-Element is representative of the structural behavior of a solid portion of masonry and has 6 degrees of freedom of rigid body and 1 degree of freedom of shear deformability. These interact with each other through interfaces discretized in nonlinear links calibrated using a fiber approach, which allow the inelastic response of the masonry to be simulated through hysteretic constitutive bonds, asymmetric in resistance and in the constitutive law, which can provide a degradation in resistance according to the fracture energy assumed or released by the masonry.