The ocean covers most of the planet's surface and just about all of the water found on Earth is found in the ocean. While the ocean is one big watery area it is divided into five parts -- also called oceans. There is the Pacific Ocean (the largest), the Atlantic Ocean, the Indian Ocean, the Southern Ocean and the Arctic Ocean. The ocean is very shallow at the shores but in some parts is incredibly deep -- so deep the sun's rays cannot penetrate down there, making it pitch black and very cold. The depths of the ocean are mostly unexplored and many strange fish live there.
The ocean is home to thousands and thousands of all types of fish. There are giant whales, ferocious sharks and all kinds of stingrays. There are millions and millions of fish from the type we eat like cod and tuna to fish we don't even know exist yet. There are fish that swim around on their own and fish that swim together in huge groups known as shoals or schools. There are brightly colorful fish and plain fish. There are dolphins and porpoises. And there are millions of tiny creatures that are almost too small to see called plankton.
The ocean is used by all sorts of other creatures as well, some that spend almost all their lives in the water and others that visit it occasionally or get their food from the ocean. There are turtles and tortoises that live in their shells, there are crabs and lobsters, there are penguins, seals and giant sea lions. There are all sorts of birds that live on the ocean or beside it and spend their days hunting for fish to eat. There are even snakes that live in the ocean, called sea-snakes. There are brightly colored plants and coral reefs which are actually made up of millions of tiny creatures
Human beings have depended on the ocean and the creatures within it for thousands of years. The ocean is very important to humans as we get a huge amount of our food from it. We have been fishing from the ocean since as long as there have been humans. We eat all kinds of fish and creatures from the sea -- even seaweed. Fishing also provides people with lots of jobs. The ocean has also been an important way to travel around the Earth, even if it's just across the bay in a rowboat, to another island in a sailboat or all the way around the world in a huge ocean liner. The ocean is also very enjoyable to swim in, look at and be beside.