This course aims to provide current understanding about extracellular vesicles (EVs) and their role in health and diseases. The EVs are known to be involved in cell to cell communication. Apart from maintaining normal cell physiology, EVs deliver messages that can drive or influence the progression of a disease. This course discusses recent advances made in the field to give an introduction on their function in health as well as in disease. This course includes four modules. Module 1 is an introduction to the course, and provides an overview of the previous MOOC on EVs “Basics of Extracellular Vesicles”. Module 2 focuses on the role of EVs in physiological conditions and gives various examples on their role in metabolism, inflammation, immunity and pregnancy and coagulation. This module also briefly covers the topic of microorganism-derived EVs such as vesicles from bacteria and discusses EVs from apoptotic and senescent cells. In Module 3, we focus on the role of EVs in cancer: how EVs can mediate communication between the tumour and its microenvironment, the functional role of immune cell-derived EVs in development of cancer, as well as the role of EVs in cancer cell proliferation, survival, metastasis and drug resistance. In Module 4, the role of EVs in diseases of the cardiovascular, haematopoietic, nervous, respiratory and urinary systems, and infectious diseases will be presented. This course is recommended for intermediate learners or anyone who is interested in the field of extracellular vesicles and their role in a particular disease including scientists, clinicians, or cell and molecular biologists who look to broaden their understanding of the field.