A Pressure Gauge is a method for measuring fluid, gas, water, or steam intensity in a pressure powered machine to ensure there are no leaks or pressure changes that would affect the performance of the system. It is also known as pressure meters or vacuum gauges. A device that uses the surface area and weight of a liquid column to measure and indicate pressure is known as a manometer. Most gauges calculate the pressure relative to atmospheric pressure as the zero point. The pressure gauge is very useful.