There are three kinds of coral reefs: fringing rees, barrier reefs, and atolls.
- Fringing reefs grow right up to the shore.
- Barrier reefs are seperated from the shore by a wide, deep lagoon.
- Atolls are coral reefs that surround a shallow lagoon. They are created when an island that is surrounded by barrier reefs sinks below the water, leaving a cicular reef, the atoll.