The book briefly presents a review on the understanding of polymer thin films, their preparation, characterization and analysis. The first chapter deals with an overview and basic concepts of polymer science. The second chapter deals with the preparation and characterization techniques such as spin coating and x-ray reflectivity. The third and fourth presents analysis and discussion on structure and swelling dynamics of ultra-thin polymeric films. The book will be useful as reference text for research scholars and teaching courses on polymer thin films.