What is desalination and how is it used to obtain potable water from salty water or sea water?

Desalination is the process of removing salt and other impurities from salty water or sea water to produce potable water. This is typically achieved through methods such as distillation or reverse osmosis, making the water safe for drinking and other uses.

A strong answer should directly address the approved learning objective to describe desalination as a method for obtaining potable water from salty water or sea water. This question belongs to Potable water within Using the Earth's resources and obtaining potable water, so the response should use that exact curriculum context rather than a generic statement. The answer is correct when it names the key idea, explains the link to potable water, and keeps the wording specific to AQA GCSE revision.