The book contains a description of the chemical structure of biological macromolecules, their size and shapes (conformation), and how the structure and the conformation determine the physical properties of such molecules. This book discusses the relationships between the chemical and physical properties of such molecules and their technological and bio-medical properties. It is designed for second or third year bachelor's students in chemistry or physics, and for first year students in master's programmes in biochemistry, biotechnology, glycobiology and bio-nanotechnology. The book will be an asset for programmes for polymer chemistry and technology. Professor Emeritus Olav Smidsr¸d, Dr. techn. is a central figure at the Department of Biotechnology, Norwegian University of Science and Technology, where he also was the director of the Norwegian Biopolymer Laboratory for 20 years. Professor Smidsr¸d has published 200 scientific papers in international journals, and was an editorial board member for three journals. He holds 15 patents dealing with the production and bio-medical uses of biopolymers. He was granted knighthood to the order of St. Olav and holds many academic distinctions for his research work. Associate Professor St¸rker Moe, Dr. ing. works at the Department of Chemical Engineering at the Norwegian University of Science and Technology where he is an expert in industrial wood chemistry. He has published numerous papers in a wide range of topics related to wood chemistry, such as cellulose chemistry, and hemicellulose behaviour in pulping processes and lignin chemistry.