Canning rings, also known as jar bands, are metal bands used in the home canning process. They fit over the top of a glass jar, holding the canning lid in place during the sealing process. These rings are essential for creating an airtight seal, which helps preserve food for long periods. After the canning process, the rings can be removed, and the jars can be stored. It's important to check the seal before using the contents, as a proper seal indicates that the food is safe to eat. Canning rings can be reused, but they should be inspected for rust or damage before each use.