Method for treating, processing and/or recycling materials, specifically plastic materials, - wherein the material is moved and mixed in a receiving container, specifically a cutting compactor, and is also heated, comminuted and/or softened, wherein the material in the receiving container remains in chunks or in particulate form and non-melted, - wherein in the receiving container, in particular in a side wall of the receiving container, in particular in the region of the level of the or the lowermost mixing and/or comminuting tool closest to the base, an opening is formed through which the pretreated plastic material can be removed from the interior of the receiving container, and wherein at least one conveyor, in particular an extruder, having at least one, in particular plasticizing or agglomerating, screw rotating in a housing, is arranged for receiving the pretreated material emerging out of the opening, - wherein the chunky or particulate material moving in the interior of the receiving container is subjected to spectroscopic and/or spectrometric inline analysis or measurement, wherein the measurement values determined in this manner are used to obtain information regarding the respectively measured material, in particular quantitative and/or qualitative characteristic variables of the respective material, - wherein at least some of the chunky or particulate material, located in the interior of the receiving container and rotating there, is excited by a physical action, in particular by electromagnetic radiation, and the measurement signals resulting as a reaction to the excitation, in particular characteristic spectra of the electromagnetic radiation scattered by the measured material, are detected, preferably spectrometrically, - wherein light is detected and analyzed in order to detect inline specific quantitative and/or qualitative characteristics of the plastic material, or changes in these characteristic variables during the process, and to draw upon them to monitor and/or control the process and/or to use these characteristic variables to control the process management in the receiving container, and/or to use the subsequent process chain. - wherein the material is moved and mixed in a receiving container, specifically a cutting compactor, and is also heated, comminuted and/or softened, wherein the material in the receiving container remains in chunks or in particulate form and non-melted, - wherein in the receiving container, in particular in a side wall of the receiving container, in particular in the region of the level of the or the lowermost mixing and/or comminuting tool closest to the base, an opening is formed through which the pretreated plastic material can be removed from the interior of the receiving container, and wherein at least one conveyor, in particular an extruder, having at least one, in particular plasticizing or agglomerating, screw rotating in a housing, is arranged for receiving the pretreated material emerging out of the opening, - wherein the chunky or particulate material moving in the interior of the receiving container is subjected to spectroscopic and/or spectrometric inline analysis or measurement, wherein the measurement values determined in this manner are used to obtain information regarding the respectively measured material, in particular quantitative and/or qualitative characteristic variables of the respective material, - wherein at least some of the chunky or particulate material, located in the interior of the receiving container and rotating there, is excited by a physical action, in particular by electromagnetic radiation, and the measurement signals resulting as a reaction to the excitation, in particular characteristic spectra of the electromagnetic radiation scattered by the measured material, are detected, preferably spectrometrically, - wherein light is detected and analyzed in order to detect inline specific quantitative and/or qualitative characteristics of the plastic material, or changes in these characteristic variables during the process, and to draw upon them to monitor and/or control the process and/or to use these characteristic variables to control the process management in the receiving container, and/or to use the subsequent process chain.