Air Travelers -- Science Background -- Pressure

Pressure is the amount of force pushing against a specific amount of area. Increasing the pressure means more force is pushing against the same area. When we stand on the ground, we are exerting pressure against the ground below our feet (and there's an equal force pushing up against our feet). If we carry extra weights, we would increase the pressure under our feet because we are pushing harder against the same area. However, if we increased the size of our shoes and spread the same force over a larger area, the pressure decreases. That's why we can step across deep snow when we wear wide snowshoes.

When an object is surrounded by a gas or liquid, it experiences pressure from all directions. A diver in the ocean can feel the water pushing inward. If the diver drops deeper into the water, the pressure increases, because the pressure depends on the total amount of water above the diver.