Immunization is a crucial part of preventive healthcare that helps protect individuals and communities from infectious diseases. It involves administering vaccines that contain weakened or inactive forms of disease-causing agents or components. Immunization activates the immune system to recognize and fight specific pathogens, building immunity and reducing the risk of contracting associated diseases. Vaccines have helped eradicate or significantly reduce the incidence of many dangerous illnesses, such as polio, measles, and tetanus. They not only protect individuals but also contribute to public health by preventing the spread of infectious diseases. Immunization is a safe and effective method that saves lives and plays a critical role in maintaining population health and well-being.