The Oceans and Sea have 75% of the world. There is high salinity. Magnesium is in Ocean water. Desalinization is where they take salt out of the water. There can't be salt in the water we drink. Most the water we get is from Oceans. Rain or Melted Snow that soaks into the ground is called groundwater. After the rivers a Lake will form because the water has to stop somewhere. A Lake that people make with dams are called reservoir. About 70% of Earths fresh water is from Ice. Glaciers and Ice sheets form when snow doesn't melt in the summer for many years. First the water is pumped through pipes. Then the water flows to a tank. Next dirt and other particles are removed. Then the water flows through filters. Finally a chemical is put in it to remove some smaller particles. Sleet forms when rain freezes when it falls.