Immunization refers to the process of triggering an immune response, encompassing both humoral and cell-mediated aspects, within the recipient. Vaccines consist of a harmless form of the targeted bacteria or virus responsible for the disease. These pathogens are rendered non-threatening through methods like inactivation, attenuation, or fragmentation, ensuring they prompt an immune reaction without causing illness. While vaccines engage the immune system, they elicit a response akin to that provoked by actual infections, yet without exposing the recipient to the disease's associated risks. Many vaccines also foster immunological memory similar to that gained from natural infections, bolstering the body's defenses against future encounters with the pathogen.