We've learned now that the water vapor that makes up clouds can come from evaporation or sublimation.
The opposite of evaporation is called condensation.
Condensation is when the water molecules inside water vapor turn from a gas to a liquid.
You can see this happen in real life if you have something like a cold glass of lemonade outside on a hot humid day.
On a hot humid day, there is a lot of water vapor in the air.
If you bring the cold lemonade glass outside, the water vapor in the humid air starts to turn to water on the outside of the glass of lemonade.
Condensation is also how clouds are made. The water vapor molecules all get bunched up together in the air until there are so many of them they start turning from gas back into tiny little drops of liquid.
(from: wikipedia - condensation)
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