Absolute humidity and relative humidity

There are two types of humidity. Absolute humidity is the measure of the mass of water present in the air at the current temperature. Relative humidity is a measure of the amount of water vapor in the air, relative to the amount needed to saturate the air at that temperature. So if the relative humidity is 80%, it means that a 20% increase in humidity would result in the air becoming saturated with water vapor. once the air is saturated, it cannot hold any more water. When this air cools, the moisture present condenses, and water droplets are formed. The temperature at which this happens is called the dew point.