Freshwater: Water with a low salt content, typically less than 1,000 milligrams per liter (mg/L). Freshwater is found in lakes, rivers, streams, groundwater, and glaciers. It is essential for drinking, irrigation, and industry.

Saline water: Water with a high salt content, typically more than 10,000 mg/L. Saline water is found in oceans, seas, and some lakes and rivers. It is not suitable for drinking without desalination, a process that removes the salt.