The sample is introduced into the high-energy heat source, causing it to vaporize and form a high-temperature plasma. As the sample atoms or ions return to lower energy states, they emit light at characteristic wavelengths. The emitted light is passed through a spectrometer, which disperses the light into its individual wavelengths. The intensity of the emitted wavelengths is measured by a detector. A computer analyses the emitted wavelengths and their intensities to identify the elements present and determine their concentrations. Quantification: Quantification is typically achieved by comparing the intensity of the emitted lines to known standards or calibration curves. This allows for the determination of the concentration of each element in the sample. OES is widely used in various industries, including metallurgy, environmental monitoring, quality control in manufacturing, and research. It is especially valuable for detecting trace elements and contaminants in materials and environmental samples.