Oceans are vast bodies of saltwater that cover about 71% of the Earth's surface. They play a crucial role in regulating the planet's climate and are home to a diverse range of life, from tiny plankton to massive whales. Oceans also provide resources like fish and seaweed, which are important for food and industry. The five main oceans are the Pacific, Atlantic, Indian, Southern, and Arctic Oceans. Each ocean has unique features, such as deep trenches and coral reefs. These underwater ecosystems are vital for maintaining biodiversity and supporting the livelihoods of millions of people around the world.