This book will be a one-stop-shop for readers seeking information on lightweight composites made from multiple materials via diverse processing technologies. The lightweight composites are featured for their potential to be basic construction units in a variety of areas, especially automotive, civil engineering, aerospace engineering, etc. Emphasis will be on how fibers or fibrous structures reinforce the composites. The subject of the book is to provide a comprehensive understanding on the raw materials, processing technologies, performance properties, and end uses of lightweight composites.