Atomic Absorption Spectroscopy (AAS) is an analytical technique used to determine the concentration of specific metals in a sample. It works by vaporizing the sample and exposing it to light from a hollow cathode lamp, which emits light at characteristic wavelengths for each element. When the light passes through the vapor, some of it is absorbed by the atoms of the element being analyzed, allowing for quantification based on the amount of light absorbed. AAS is widely used in various fields, including environmental monitoring, food safety, and clinical analysis. It is valued for its sensitivity and ability to detect trace levels of metals, making it an essential tool in laboratories for quality control and research purposes.