In recent years, there has been no dearth of elegant works dealing with the subject of spectroscopy at the undergraduate and postgraduate levels. There are, however, very few books which hold the interest of the inquisitive students. The second revised and enlarged edition of this book encompasses authoritative information on major issues of the subject. The order of the topics covered in this book can do full justification for Indian students. Each topic covered in this book has been self- sufficient in itself and has been explained with a large number of diagrammatic presentations. Every topic has been described in the light of modern developments in a simple language and elegant style. An attempt has been described in the light of modern developments in a simple language and elegant style. An attempt has been made to include the latest developments in the instrumentation of various spectroscopic techniques.