Clouds can be placed into three main groups:

High Altitude clouds:

These are located 20,000ft or higher above the land surface. Cirrus, Cirrostratus, and Cirrocumulus are the cloud types found here.

Middle Altitude Clouds:

These are found between 6,500ft to 20,000ft above the land surface. Altostratus and Altocumulus are the cloud types found here.

Low Altitude Clouds:

These cloud types can be found from ground level to about 6,500ft above it. They include Stratus, Stratocumulus, and Nimbostratus clouds.

Vertical Clouds:

These are clouds that extend from the lower to the higher altitudes of the atmosphere. They form by thermal convection or frontal lifting, sustained by the powerful convectional current that holds and push the moisture in the clouds further upward. An example of a vertical cloud is the Cumulonimbus cloud.

Foggy Clouds:

These form close to the ground. Sometimes they make visibility very poor such that you can hardly see more than 60 away.

Cloud Names:

There are four primary clouds, which have specific features of their own. These are Cirrus (meaning curl), Stratus (meaning spread over), Cumulus (meaning pile or heap), and Nimbus (meaning water or rain-bearing). They are often combined with many other names to describe other secondary cloud types.