Clouds are made of very small droplets of water, or ice crystals. They are so light that they float in the air.
Water evaporating from the surface of the earth, lakes, seas and oceans rises to the top. In the higher parts of the atmosphere, the steam cools down and the phenomenon of the so-called condensation. It consists in changing the water vapor into drops of water. The lingering water and ice particles form clouds.
There are three main types of clouds, cumulus clouds, layered (stratus), and pinnate (cirrus). What kind of cloud will be created depends on many factors. If a small amount of warm air rises quickly, it forms a cumulus cloud. Air rising slowly and steadily is likely to produce a layered cloud. Circular clouds are formed by strong winds in the upper atmosphere.