Materials science is a vast field of study. It mostly deals with interatomic connections within molecules, without paying much attention to fragile intermolecular interactions. However, the varied structures are, in fact, the consequence of weak ordering because of noncovalent interactions. For self-gathering to be feasible in soft materials, it is obvious that the forces between molecules must be more fragile than covalent bonds among the atoms of a molecule. The fragile intermolecular interactions accountable for molecular ordering in flexible materials consist of hydrogen bonds, management bonds in ligands and compounds, among others. Current developments in nano science and technology offer certain well-built arguments to sustain the significance of the subjects discussed in this book. The essential and productive features connected to molecular interactions are analyzed. This book intends to provide some useful information for students and experts so as to understand the subject better.