Two-dimensional materials created ab initio by the process of condensation of atoms, molecules, or ions, called thin films, have unique properties significantly different from the corresponding bulk materials as a result of their physical dimensions, geometry, nonequilibrium microstructure, and metallurgy. Further, these characteristic features of thin films can be drasti­ cally modified and tailored to obtain the desired and required physical characteristics. These features form the basis of development of a host of extraordinary active and passive thin film device applications in the last two decades. On the one extreme, these applications are in the submicron dimensions in such areas as very large scale integration (VLSI), Josephson junction quantum interference devices, magnetic bubbles, and integrated optics. On the other extreme, large-area thin films are being used as selective coatings for solar thermal conversion, solar cells for photovoltaic conver­ sion, and protection and passivating layers. Indeed, one would be hard­ pressed to find many sophisticated modern optical and electronic devices which do not use thin films in one way or the other. With the impetus provided by industrial applications, the science and technology of thin films have undergone revolutionary development and even today continue to be recognized globally as frontier areas of RID work. Major technical developments in any field of science and technology are invariably accompanied by an explosion of published literature in the form of scientific publications, reviews, and books.