There are several types of vaccines, each designed to provoke an immune response in a different way. The main types include: - Inactivated vaccines: Contain killed pathogens. - Live-attenuated vaccines: Contain weakened forms of the pathogen. - Subunit, recombinant, and conjugate vaccines: Contain parts of the pathogen (like proteins). - Toxoid vaccines: Contain inactivated toxins produced by the pathogen.