OBJECTIVE: Theoretical aspects and the applications of different types of atomic and molecular spectroscopic methods. The molecular spectra contain important information about the structure of the molecule. In this Book you will learn that how the information available from different types of molecular spectra can be used for the structure elucidation of the Organic molecules. In this context we will use the information available from UV-VIS, IR, 1H-NMR and MASS spectrometry. thus, aims to integrate the information available from different types of spectral methods and apply this knowledge to arrive at the structure of a molecule.