 The present review outlines recent progress in the study of exosomes, including their biogenesis, molecular composition, and potential users' diagnostic and therapeutic tools. Exosomes are nanosized biovesicles that carry cell-specific cargos and can be taken up by neighboring or distant cells, reprogramming them upon their bioactive compounds. The regulated formation of exosomes and specificity of their cargo make them valuable diagnostic and therapeutic tools, with potential applications in drug and gene delivery. Further research is needed to understand the subcellular components and mechanisms involved in exosome formation and targeting to fully elucidate their physiological activities. This article was authored by Yuan Zhong, Yun Feng Liu, Haiying Liu, and others.