Clouds form by the condensation of water vapour around tiny particles like dust in the atmosphere.

Clouds form through the process of condensation of water vapor in the atmosphere. This process involves several steps that lead to the creation of the fluffy white formations we see in the sky.

Evaporation of Water:
- The first step in cloud formation is the evaporation of water from the Earth's surface. This water vapor rises into the atmosphere.

Condensation of Water Vapor:
- As the water vapor rises, it cools down and condenses into tiny water droplets or ice crystals around tiny particles in the air, such as dust or salt. These droplets gather together to form clouds.

Formation of Cloud Droplets:
- When the air temperature is cool enough, the water droplets within the cloud combine and grow in size. This process is known as coalescence.

Types of Clouds:
- Depending on the altitude, temperature, and other atmospheric conditions, different types of clouds are formed, such as cumulus clouds, stratus clouds, and cirrus clouds.

Role of Humidity:
- High humidity levels in the air can lead to the formation of thicker clouds with more water droplets, while lower humidity levels may result in thinner clouds.

Cloud Characteristics:
- Clouds can vary in shape, size, and color, depending on the weather conditions. They can also produce precipitation when the water droplets within them become too heavy and fall to the ground as rain, snow, or hail.
In conclusion, clouds form through the process of condensation of water vapor in the atmosphere, where water droplets or ice crystals gather together to create the visible formations we see in the sky.