pound force per square inch
Pound force per square inch (psi) is a unit from the Imperial system defined as the pressure resulting from a force of one pound-force applied to an area of one square inch. It is used in various applications such as tire pressure and hydraulic systems.
Pascals
Pascals (Pa) are the SI units of pressure named after the French mathematician Blaise Pascal. It is defined as one newton per square meter (N/m²). Since the pascal is a relatively small unit, kilopascals (kPa), megapascals (MPa), and gigapascals (GPa) are often used for practical applications.