The four cloud families to know are:
- cumulus: heaped clouds, white and puffy, with a flat base, like balls of cotton wool;
- stratus: layered clouds, a flat grey sheet that covers the whole sky, low down;
- cirrus: wispy clouds, thin white threads or curls, very high, made of ice;
- cumulonimbus: the storm cloud, a huge tower that rises from a low dark base to a very great height, and whose top often spreads out flat.



