Non-infectious diseases refer to medical conditions or illnesses that are not caused by pathogens such as bacteria or viruses. These diseases are typically chronic and long-lasting, and may be caused by a variety of factors including genetics, lifestyle choices, environmental exposure, and underlying health conditions. Common examples of non-infectious diseases include heart disease, cancer, diabetes, and autoimmune disorders. Research in this area focuses on understanding the causes, risk factors, prevention, and treatment of these diseases in order to improve the overall health and well-being of individuals.