The vaccine comes from the Latin vacca (cow) and vaccinia (cowpox). Vaccines are antigenic ingredients used to produce active immunity to a disease so as to prevent or reduce the influence of infection by natural or wild organisms.

       Vaccines can be viral or bacterial strains that have been weakened so they do not cause disease. Vaccines can also be dead organisms or purification products (proteins, peptides, virus-like particles, etc.). Vaccines will prepare the human or animal immune system to defend against certain pathogens, especially bacteria, viruses, or toxins. Vaccines can also help the immune system to fight degenerative cells (cancer).

     Vaccination is given to stimulate the body's immunological system to form specific antibodies so that it can protect the body from disease attacks which can be prevented by vaccine. There are several types of vaccines. However, whatever the type is,they have the same purpose, which is to stimulate the immune reaction without causing disease.