Pressure is an important concept in hydraulics because it is what allows the system to transmit force and motion. When a fluid is subjected to pressure, it will transmit that pressure equally in all directions. This principle is what allows hydraulics to transmit force over long distances or when high levels of force are required.

In a hydraulic system, pressure is generated by a pump, which uses mechanical energy to pressurize the fluid. The pump is usually powered by an electric motor or an internal combustion engine. As the pump operates, it generates flow and pressure in the fluid, which is then transmitted through a system of tubes or hoses to the various components of the system.

The pressure in a hydraulic system is typically measured in pounds per square inch (psi). The higher the pressure, the more force the system can transmit. However, it is important to note that the pressure in a hydraulic system is limited by the strength of the components and the ability of the fluid to withstand the pressure. If the pressure becomes too high, it can cause damage to the system and lead to failure.

In summary, pressure is what allows a hydraulic system to transmit force and motion.