Definition: Vaccination is a type of medical procedure that involves introducing a weakened form of an infectious disease into the body to stimulate immune responses. This process helps to prevent the spread of infection and protect against future infections. In immunology, vaccination refers to administering a vaccine or other treatment to a person who has been infected with a particular virus or bacteria to help fight off the infection. Vaccines can be administered orally, subcutaneously (under the skin), intravenously (through a vein), or