The clouds are composed of water vapour in the air. The clouds are divided into four categories on the basis of appearance and height.
They are
- Cirrus cloud
- Stratus cloud
- Cumulus cloud
- Nimbus cloud
1. Cirrus cloud: These clouds appears like a silver grey fish at a very high altitude in the sky. These may not give rain.
2. Stratus cloud: They are grey in colour and are spreadout. They may give small shower.
3. Cumulus cloud: It looks like a burst cotton and gives convectional rainfall. These clouds are associated with rainfall lightning and thunder.
4. Nimbus cloud: It appears as dark or grey in color. It gives heavy rainfall. It is called vertical or rain clouds.