Torsion tests twist a material or test component to a specified degree, with a specified force, or until the material fails in torsion. The twisting force of a torsion test is applied to the test sample by anchoring one end so that it cannot move or rotate and applying a moment to the other end so that the sample is rotated about its axis. The forces and mechanics found in this test are similar to those found in a piece of string that has one end held in a hand and the other end twisted by the other. The purpose of a torsion test is to determine the behavior a material or test sample when twisted or under torsional forces as a result of applied moments that cause shear stress about the axis. Measurable values include ultimate torsional strength and these values are not the same as those measured by a tensile test and are important in manufacturing as they may be used to simulate the service conditions, check the product’s quality and design, and ensure that it was manufactured correctly. The two common forms that torsion testing include failure and operational. A torsion test for failure requires that the test sample be twisted until it breaks and is designed to measure the strength of the sample. And finally, operational testing measures the material’s performance under the expected service conditions of its application. Many materials experience torques or torsional forces in their applications and so will benefit from or require torsion testing. Materials used in structural, biomedical and automotive applications are among the more common materials to experience torsion in their applications. These materials may be composed of metals, plastics, woods, polymers, composites, or ceramics among others and commonly take the forms of fasteners, rods, beams, tubes and wires.