On Earth, there is more ocean than land. The Pacific Ocean is the biggest ocean. It’s bigger than Africa!
Did you know that there are mountains and valleys under the ocean? Some of these mountains are bigger than the biggest mountains on land. In the deepest parts of the ocean, the water is 10 kilometers deep.
The water in the ocean is always moving. Waves hit the land and break the rocks. Sometimes, big pieces of rock fall into the ocean. They leave big cliffs, like the beautiful Uluwatu Cliffs in Bali in Indonesia.
Where the ocean is warm, we sometimes find coral. Coral is made of millions of very small animals that make hard covers around themselves. When the animals die, the hard covers make the coral reef.
The Great Barrier Reef near Australia is the biggest coral reef in the world. It’s 2,600 kilometers long. Sea turtles, dolphins, and many other amazing animals live there.
In some places, where the coral reef is very big, it comes out of the water. It makes a small island.