1. A method of investigating and identifying the nature of a material to be worked and for making available at least one operating parameter for the optimized pre-setting of a working device, comprising the steps of: detecting a shock wave generated or induced in a tool of the working device, before or at the beginning of a working process; measuring the shock wave signal; and algorithmically extracting and algorithmically evaluating at least one distinguishing feature (M1 to M4), characteristic of the material, from the shock wave signal, for classifying the material.