Spectroscopy is an important scientific technique in analytical chemistry. It involves studying the interaction between matter and electromagnetic radiation to identify the chemical composition and physical properties of different substances. Due to its accuracy and sensitivity, spectroscopy has become an essential tool in chemical, medical, and forensic laboratories. The principle of spectroscopy is based on the absorption, emission, or scattering of electromagnetic radiation by matter. Different substances respond to radiation according to their molecular structures and energy levels, allowing scientists to obtain valuable information about their chemical properties. Several types of spectroscopy are commonly used in scientific analysis, including Ultraviolet-Visible Spectroscopy (UV-Vis), Infrared Spectroscopy (IR), and Nuclear Magnetic Resonance Spectroscopy (NMR). Each technique provides specific information about chemical compounds and their molecular structures. In forensic science, spectroscopy is used to examine certain drugs, toxic substances, dyes, and chemical residues collected from crime scenes. Infrared spectroscopy can help identify polymers, fibers, and paints, while atomic spectroscopic techniques are useful for detecting selected metallic elements in forensic samples. These techniques provide valuable scientific information that helps forensic experts compare evidence and determine its chemical composition. However, additional analytical methods may sometimes be required to confirm the identity of unknown substances. In conclusion, spectroscopy represents an advanced scientific approach that combines physical and chemical principles. It plays an important role in improving laboratory investigations and increasing the reliability of forensic chemical analysis.