CoachSalt water has a lot of salt dissolved in it: it is the water of the oceans and the seas. Fresh water has very little salt: it is the water of rain, of most rivers and lakes, of the ice and the snow, and of springs.
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Example 3.3 (How salty is the sea?)
In a bottle holding one kilogram of sea water — about one litre — there are about 35 grams of salt. If we let all the water evaporate, the salt stays behind as white crystals at the bottom. That is how sea salt is made in salt marshes by the sea, where the sun and the wind slowly dry out shallow pools of sea water.