The group theory is a powerful tool that is used to determine symmetry of molecules. It is a key component in the present-day Physical Sciences, Chemical Sciences, Mathematics, Statistics and Computer Sciences. Groups - “set of all the permutation of the roots of an algebraic expression that exhibit the characteristics that the combination of any two of these permutations belongs to the set.” Group theory has a huge number of applications in the real world.     
                                  
Group theory is not only confined to determination of molecular symmetry but also symmetry of molecular orbitals, atoms, rotation and vibration of bonds, and is thus very useful in spectroscopy. The symmetry of molecules / molecular orbital provides information regarding the positions of orbitals in various energy levels and the molecular transitions in them. 

This book is elementary presentation of group theory for interpretation of molecular structure.
While writing the book, I have endeavored to express the matter in a simplified and lucid manner. I believe that this book will be very useful for the under graduate and post graduate students.