Atmosphere, which surrounds globe, by means of its gravity force, influences the Earth. This is called the atmospheric pressure. Atmospheric pressure changes in any part of the Earth. Atmospheric pressure settles with height. It is closely connected with the air thermal changes. In connection with distinctions of pressure, the air, which is contained in atmosphere, is moving always. For each hemisphere there are the following types of air mass: equatorial, tropical, temperate and arctic. Differences of the atmospheric pressure condition the motion of air. Motion of air in horizontal direction is called the wind.