FTIR spectroscopy provides molecular fingerprinting through analysis of infrared light absorption. It can identify unknown materials and quantify components in mixtures. Fourier transform infrared spectroscopy uses an interferometer to record an interferogram, which is mathematically converted using Fourier transform into an infrared spectrum. This allows identification of molecular structures based on their vibrational and rotational frequencies. FTIR has advantages over dispersive infrared spectroscopy such as increased speed and sensitivity. It has wide applications including polymer analysis, environmental monitoring, food quality testing, and quality control.