"Soft matter" is nowadays used to describe an increasingly important class of - terials that encompasses polymers, liquid crystals, molecular assemblies building hierarchical structures, organic-inorganic hybrids, and the whole area of colloidal science. Common to all is that ?uctuations, and thus the thermal energy k T and B entropy, play an important role. "Soft" then means that these materials are in a state of matter that is neither a simple liquid nor a hard solid of the type studied in hard condensed matter, hence sometimes many types of soft matter are also named "c- plex ?uids. " Soft...