Clouds are a visible mass of Water Vapour in the atmosphere of a planet.
List of Cloud Families
Family A (High)
Cirrocumulus - a cloud layer which sits near cirrus clouds and can also produce a weather system.
Cirrostatus - a cloud layer which can produce halos due to the Sun's interaction with the cloud. A cloud like that thickens sometimes into a bigger cloud like an Altostratus and may signal a Warm Front.
Family B (Middle)
Altocumulus - a medium-leveled cloud which can produce light Precitipation.
Altostratus - a cloud which typically signals the overhead of a warm frontline.
Family C (Low)
Stratocumulus - a low-leveled cloud which can be seen from the windows of a plane. It contains light precitipation. A Stratocumulus can signal a cold front.
Stratus - a low-leveled cloud layer which sometimes reasembles Fog.
Family D1 (Vertical)
Cumulus - Clouds with a heaped shape and a flat base.