Fractography is the detailed analysis of a fracture surface to determine the cause of the fracture and the relationship of the fracture mode to the microstructure of the material. Fractography techniques are used to identify the origin of a crack and to determine what type of loading caused the crack to initiate. These techniques are also used to establish the direction of crack propagation and the local loading mode, which drove the crack. Fractography is, perhaps, the most important analytical approach used by materials scientists in attempting to establish structure-property relationships involving strength and failure of materials.