Ultraviolet spectroscopy is measured an important tool in analytical chemistry. In fact, this is one of the most ordinarily used techniques in clinical as well as chemical laboratories. This tool is used for the qualitative analysis and identification of chemicals. However, its main use is for the quantitative determination of different organic and inorganic compounds in solution. Basically, spectroscopy is related to the interaction of light with matter. As light is absorbed by matter, the result is an increase in the energy content of the atoms or molecules. The absorption of visible light or ultraviolet light by a chemical compound will produce a different spectrum. This is not a text book, but a reference book, useful for graduate and post-graduate chemistry students of all Universities. We provide a wide coverage of basic concept of UV spectroscopy and calculated theoretically value of various organic compounds.