Lagoons typically have one or more restricted connections to the ocean, known as inlets. The boundary of a lagoon is usually defined by the land surrounding it, including any islands or sandbars that may be present at the inlet. In addition, the boundary may also be defined by the depth of the water, as lagoons are often shallow bodies of water. The boundary of a lagoon can also be defined by the types of plants and animals that live in it. For example, some lagoons may be home to mangroves or seagrasses, while others may be home to coral reefs.