This document discusses different types of illnesses including infectious and non-infectious diseases. Infectious diseases can be transmitted through personal contact, droplets, contaminated objects, animals, food or water. They are caused by bacteria, viruses, protozoans or fungi. To prevent infectious diseases, people should wash their hands, brush their teeth, clean cuts, keep pets healthy, wash produce, avoid walking barefoot, and get vaccinations which contain weakened versions of viruses or bacteria to help the body build immunity. Non-infectious diseases can be prevented through a balanced diet, regular exercise, sufficient sleep, following safety rules, and accepting oneself and others.