What's the difference between Absolute, Gauge and Barometric pressures?

absolute pressure - The actual pressure at a given position is called the absolute pressure, and it is measured relative to absolute vacuum (i.e., absolute zero pressure). gage pressure - Gage pressure is the pressure relative to the atmospheric pressure. In other words, how much above or below is the pressure with respect to the atmospheric pressure. 

atmospheric pressure - The atmospheric pressure is the pressure that an area experiences due to the force exerted by the atmosphere. 

absolute pressure is the another name of barometric pressure

gauge pressure mean that atmospheric air pressure

absolute mean perfect pressure

Absolute pressure = gauge pressure + atmospheric pressurewhere, gauge pressure is the actual pressure of that environment which is other than atmospheric pressure or it is with respect to the atmospheric pressure.

andAbsolute pressure is also known as Barometric pressure. 

Absolute pressure is the measured pressure with respect to a perfect vacuum.

Gauge pressure is the measured pressure with respect to ambient or atmospheric air pressure. 

Therefore, Absolute pressure = Gauge pressure + ambient air pressure

Absolute pressure is also called as Barometric pressure; i.e. absolute pressure = barometric pressure