The National Institutes of Health, or NIH for short, is an organization in the United States that helps scientists and doctors find new ways to keep people healthy. The NIH is like a big team of people who work together to figure out how to keep you and your family from getting sick. They work on all sorts of things, like figuring out what causes different diseases and how to cure them, or coming up with new treatments for conditions like cancer, heart disease, and diabetes. The NIH also helps to fund research to help people learn about different health problems and find ways to keep them from happening. It's kind of like a big group of doctors and scientists who all work together to help make sure we all stay healthy!