Composite materials are made from at least two different materials with significantly different properties and behavior. When such materials are combined, the produced composite has completely different characteristics compared to the individual components. In ancient Egypt, the earliest composite materials where created to form bricks out of mud and straw for building constructions. Polymeric composites are steadily growing and are one of the most promising material classes, which have the opportunity to deal with new challenges approaching from the market. These materials are often stronger, lighter or less expensive when compared to traditional materials, but the demands and needs are getting more diverse and complex. Modern composites comprise the incorporation of filler in micro and nanoscale, as well as the construction of specific structure - especially the imitation of nature - to create new or improved material properties. This book gives an overview of the scientific investigations carried out in recent years. The topics discussed are forging an arc over different kinds of composite materials such as composites based on commonly available polymeric raw materials, but also composites based on biological raw materials as well as the achievable material properties comprising mechanical, electrical, structural and tribological properties. Additionally, the book is also shedding light on the construction and structuring of such composites using nature as an inspiring example.