0orksecurity 10 years ago Assuming by "disease" you mean "infection": Some of them eat you, some of them poison you, some of them make it hard for you to feed yourself either by stealing resources you need or simply by disrupting your body's normal operation.But there are other kinds of diseases too. Chronic poisoning can be treated as a kind of disease. Sometimes the body just malfunctions -- an allergy is a simple example of that, cancer is a more complex example. Sometimes age-related malfunctions are considered diseases. Sometimes genetic or developmental problems are considered diseases.If you want to learn more, there's a huge amount of information available -- ask your teachers and librarians for suggestions. If you're interested in animals as well as medicine I *highly* recommend the James Herriot books (All Things Great And Small and the others he has written). Herriot knows how to tell a good story, and he does a very nice job of describing what it's like to be a veterinarian, including what sicknesses the animals are dealing with and how they were treated at the time.If you're specifically interested in human medicine, I'd recommend trying to get your hands on the books by Berton Rouche (The Incurable Wound, for example). Rouche wrote his essays almost in the form of medical mysteries, starting with a specific patient to illustrate the disease, then describing what it does to the body and how people have treated it over the years. If you're young and/or impressionable these can be a bit scary, but they really are very well written and -- like Herriot's books -- each chapter is really a short essay of its own so they're easy to read a bite or two at a time.