Your family and teachers may have told you to wash your hands with soap and hot water. This is to the spread of bacteria. Bacteria are tiny that live in your body and in the air, water, and soil. Bacteria are under a microscope. It would take one bacteria to cover the head of a pin. Bacteria may be , but they can be very powerful. Some bacteria can cause such as a sore throat or cavities in your teeth. Not all bacteria are harmful. Your body has some good bacteria to help you food. Without bacteria your intestines would not be able to gain the that they need from food or get rid of the waste they do not need. Some bacteria are also used by to make medicine. In addition, they are used to make food such as cheese and . You should always wash your hands to ensure you do not bacteria.