Explain relative humidity?

Humidity is the amount of availability of water vapour in the atmosphere. Humidity is expressed through the concept of relative humidity. The relative humidity is the ratio between the two things:

• The maximum water vapour that the air can hold at a given temperature and pressure, and

• The actual amount of water vapour it holds at any given time.

Relative humidity increases with a decrease of temperature or addition of water vapour. Relative humidity decreases with an increase in temperatures and decrease of water vapour. The critical temperature at which saturation level reached is called dew point. If the atmosphere has 100% relative humidity, it is known as the saturation level. When the relative humidity exceeds 100%, the excess of water vapour present in the atmosphere gets condensed as minute droplets of water.