The document describes the different types of clouds, including cumulus clouds which come in three varieties, cumulonimbus clouds which form under warm moist conditions and indicate thunderstorms, stratus clouds which form from cooling air masses and cause fog or mist, stratocumulus clouds which have a textured puffy appearance, altocumulus clouds which are high in the sky, altostratus clouds which cause pretty sunsets, nimbostratus clouds which form from altostratus and bring steady precipitation, cirrus clouds which are the highest ice crystal clouds, cirrocumulus clouds which also consist of ice crystals, and cirrostratus clouds which are difficult to see but produce optical effects.