The field of extracellular vesicles (EVs) has progressed immensely in recent times with evidences highlighting their importance in physiology and pathology. This book entails extensive reflective literature on many subtypes of EVs including exosomes, exomeres, ectosomes, apoptotic vesicles, bacterial EVs and fungal EVs. The book further discusses the biogenesis and secretion of these EVs, detailing the biological pathways and proteins involved. Research investigating the biological functions of EVs is rapidly increasing and the current knowledge around their role in progression of diseases such as cancer, neurodegeneration and metabolic disorders is discussed in multiple chapters. The implications of EVs in intercellular communication and the significance of biologically active cargo carried within these EVs are further examined. Moreover, the numerous applications of EVs in diagnostics and treatment of diseases are reviewed in detail, particularly their potential as biomarkers and drug delivery vehicles. Taken together, this book is a compilation of the key implications of EVs that are secreted by virtually all cell types. Readers will gain a perspective into the biology, functions and applications of EVs and their constantly evolving knowledge base.