Saltwater is water that contains a high concentration of salt, primarily sodium chloride. It makes up about 97% of the Earth's oceans and seas, giving marine life a unique environment to thrive. The salt in saltwater comes from rocks and soil, which release minerals through weathering and erosion. This salty water is essential for many organisms, including fish, coral reefs, and marine mammals. In addition to supporting diverse ecosystems, saltwater plays a crucial role in regulating the Earth's climate. It helps distribute heat around the planet through ocean currents, influencing weather patterns. Saltwater is also important for human activities, such as fishing, shipping, and recreation, making it a vital resource for economies worldwide.