With the rapid advancement in micro and nano-scale composite technologies, there is an increasing need to understand their mechanical, thermal, and structural behavior to design the next generation of materials for aerospace, automotive, biomedical, and industrial applications. The book is organized into twelve chapters, each focusing on specific innovations and methods in micro and nano composites. It begins with an introductory chapter on the basic concepts of micro and nano composites, setting the stage for more complex evaluations in later chapters. Then it delves into the mechanical and thermal properties of composites enhanced by graphene nanoparticles and explores hybrid composites using natural fibers like crab shell and jute. The advancement of 3D-printed composites, specifically carbon fiber-reinforced PLA, is covered using the Taguchi method. Subsequent chapters investigate the development of biocomposite materials using hemp, kenaf, and nut shell powders, alongside studies on metal matrix composites, wear characteristics, and surface engineering using micro powders and nanoparticles. Key topics like friction stir processing and the integration of micro metal particles in additive manufacturing provide insights into both fabrication techniques and material behavior. The book also features research on hybrid composites, such as titanium, molybdenum, and vanadium for agricultural applications and magnesium-based materials reinforced with nanoparticles for biomedical uses.