If on a Sunny day, a clean empty glass to put upside down on dug the garden or on the lawn with grass, then after some time you notice an interesting phenomenon: dry transparent inner wall of the glass will be designed to blur, and outside the glass will remain completely dry.
What happened and how can we explain the appearance of visible glass eye water droplets? Water molecules that reside on the surface of the soil and the plants, all the time we rise up together with air and cooled, deposited on the internal walls of glass, wetting it.
Water molecules evaporate grass and soil surface and form pairs in the glass that stands on the lawn upside down.
If the air contains such a quantity of water vapor, what are possible at a given temperature, it is called saturated. And if it is cooled below this temperature, the portion of the smallest droplets of vapor stick. The temperature at which this occurs is called the dew point. The air that has a temperature above the dew point, is called unsaturated. When the air is cooled below the dew point, the movement of the molecules of moisture in it slows down and drops are deposited on the cold walls of the inside of the glass. Outside of its molecules continue to rise. They make her invisible to us the way to heaven - they vanished.
The process by which water from the gas again becomes a liquid is called condensation. We often see it in everyday life, for example when misted window glass, glasses or car.