In hydraulic systems, power is transmitted and controlled by pressurized fluid in a closed circuit. A pump is a device that converts rotary mechanical power into fluid power. A motor is a device that converts fluid power into rotating mechanical power.
JIS B 8383:2000 history
2005JIS B 2292-1:2005 Hydraulic fluid power -- Dimensions and identification code for mounting flanges and shaft ends of displacement pumps and motors -- Part 1: Inch series shown in metric units