The Great Barrier Reef has been the subject of much bad news in recent years — coral bleaching and heatwaves, cyclone damage, and poor water quality.
It's easy to forget the reef is still a magical place.
It's home to over 1,000 species of fish, many not found anywhere else in the world, as well as turtles, whales, dolphins and a huge variety of invertebrates.
The creature that makes the reef the ecological and cultural icon it is today — literally makes it — is coral.
There are over 600 species of coral on the reef, and the two main types are hard and soft corals.
Hard corals are the reef's building blocks — producing a calcium carbonate skeleton to support themselves to add to the reef structure.
Soft corals don't have this hard skeleton, and appear more plant-like than animals.
Both hard and soft corals are made up of thousands of tiny coral polyps, living together in a colony.
So there are some of the basic facts. Now, test your coral knowledge with this quiz!
