Coral is often mistaken for a rock because of its hard surface! Many think it is a plant because it is rooted in the ground. Coral is a group of animals!! Different from rocks, coral is alive. Unlike plants, corals do not make their own food. A coral is actually made up of thousands of tiny animals called polyps! These tiny animals use limestone from the seawater to build a hard skeleton around them. That protects the polyps and also makes the coral hard! Coral reefs only make up a small part of the ocean, but they host up to 25% of marine life! Coral reefs give animals food and shelter!