Air pressure is when air molecules push down on you. The air from the atmosphere takes up space, so it has mass (weight). The more atmosphere above you, the more the air pressure. There is actually 14.7 pounds per square inch of your body pushing down on you right now!! That means that your whole body is having about 7 tons of air pushing down on you! You can’t really feel the air pressure because your body is pushing outward, the opposite direction of the air pressure. Since these molecules are so tiny and there is so much air around us, there are more molecules of air in and around you than there are grains of sand on Earth!!