Rheometers and universal testing machines are used to measure material properties like shear modulus, viscosity, Young modulus, tensile strength, etc. Commonly studied systems include polymers with complex architectures, nanocomposites, synthetic and biological gels. Various tests are performed to address specific research questions. For example, mechanical spectroscopic measurements are applied for solving problems in which the contribution of particular molecular motions or structural rearrangements in the polymer to the mechanical response of the material are of interest. Rheological measurements are performed in order to characterize flow properties of polymer melts and polymer solutions. Large deformations of polymers in solid or rubbery states are studied in order to deduce deformation mechanisms or quantify the material strength.