Cloud formations have always been observed by people, many centuries before our time. People were always fond of clouds. They always wondered why some clouds were dark and others were white and fluffy, and why some clouds are so up high and others were so low that they looked reachable by the human hands.
The most recent classification of clouds was accomplished by the World Meteorological Organization in 1956. This organization lists 10 basic kinds of clouds that are subdivided into species according to their outer shape and inner structure. In addition, cloud varieties are discussed according to arrangement and transparency. There is a height classification which are called high, middle, and low altitudes. The different kinds of clouds are found in these three divisions according to the clouds' altitude.
First, we have the high clouds that range in altitude from 16,500 to 45,000 feet. In this division we have the cirrus, cirrocumulus, and cirrostratus clouds. A cirrus cloud appears in delicate, feather-like bands that are not attached to each other, and is usually white with no shading. Cirrocumulus clouds appear like very small round balls or flakes. The cirrocumulus clouds sometimes form a pattern of a buttermilk sky. The cirrostratus clouds sometimes form tangled webs or thin whitish sheets. A large ring or halo is sometimes seen around the sun or moon when the cirrostratus covers the sky.
The middle layer of clouds range in altitude from 6,500 to 23,000 feet. The altocumulus, altostratus, and...