Since the ancient days of research polyphenolic compounds have found a variety of use in medicinal chemistry and presently have found their applications in material research. There is a diverse interest in studying polyphenolic-based materials ranging from enzymes to plastic materials. However, there is no unified approach towards these studies to correlate structures with the different types of properties in order to implement such studies in applied engineering. This book presents a unified approach on synthetic and natural polyphenolic compounds in different forms and elaborate their properties with selective examples.