Air Pressure

Air pressure is the force exerted by the weight of the air molecules in the Earth's atmosphere on a given area. It results from the constant movement and collisions of these molecules, which are denser near the ground and thinner higher up. When the air is dense, pressure is higher; when it is less dense, pressure drops. Changes in air pressure influence weather patterns, such as storms and high-pressure systems, and affect how things like airplanes and hot air balloons operate. In essence, air pressure is the invisible force of the atmosphere pressing against everything around us.