Our comprehensive guide gives you the savvy on the sea. Want to know more about gyres, tsunamis and bioluminescence? Browse through the infobursts for an explanation of the terms used.
Coral reefs have been called the tropical rainforests of the sea. Like their counterparts on land, these vibrant ecosystems are living structures that support a quarter of the ocean's life. Some coral reefs are 25 million years old. Find out why they might not be around much longer.
If you're looking for a particular marine animal - from the biggest whales to the smallest shrimps, you'll find them in our animal facts