Microbes are essential for maintaining life on Earth. They comprise more than 50 per cent of the life forms on our planet, yet only around 1 per cent have been identified and studied. Infectious microorganisms, including bacteria and viruses, can attack our bodies and we rely on our immune system to protect us. Thus the relationship between microbes and immune cells is critical for our survival. The University of Otago is the only institution in New Zealand offering bachelor's degrees in both Microbiology AND Infection and Immunity. The courses provide insights into the unseen world of microbes and the immune system, and an understanding of the practical applications arising from their study. Microorganisms are everywhere in our bodies, our food, the air, soil, and water. Because they're everywhere, they're involved in almost every aspect of our lives. They are used in producing foods such as cheese, wine, and beer, as well as many pharmaceutical, chemical and agricultural products. They are important for soil fertility and the decomposition of materials but can cause major diseases in humans, animals and plants. The harmful effects of some microorganisms link microbiology with immunology. Immunologists investigate how we can protect humans and animals from infectious diseases by using vaccines, and the role of the immune system in non-infectious diseases such as cancer.