According to Reference.com, "fluid pressure" is defined as the pressure exerted by a fluid at a given depth. The weight of the liquid acting on a unit area combined with pressure acting on the surface of the liquid determines the amount of liquid pressure.
Fluid pressure is affected by pressure and depth. An object placed at higher depth experiences more pressure than a similar object at a lower depth. Fluid pressure is not affected by the volume of liquid, nor can the volume of liquid be changed by pressure. Instead, liquid pressure is dependent on the density of the fluid. Liquid pressure also refers to the pressure exerted by gases. For instance, air pressure in the atmosphere decreases as altitude increases, which is why airplanes have pressurized cabins.
Fluid pressure acts perpendicular to the surface of the liquid and is the force that allows aircraft to fly and ships to float. When determining liquid pressure, the atmospheric pressure on the surface of the liquid must also be taken into account in order to calculate the total pressure of a liquid. A Pascal is a unit of pressure in the metric system that is used to measure the amount of pressure exerted by a liquid.