Oceans cover over 70% of the earth's surface and are home to many types of fish, mammals, and plants. The oceans of the world are some of the last uncharted places of the earth, with depths up to a mile below the earth's land surface. Oceans are large salt-water bodies connected across the earth. The ocean floor is made up of shelves, plains and mountain ranges.
Oceans of the world are connected, and water moves between them through currents. There are surface and deep-water currents moving water between different oceans. Waves and tides are also ocean movements and have a great impact on the earth, which edges the oceans.