What does a solenoid do in pneumatic and hydraulic?

In pneumatic and hydraulic systems, a solenoid acts as an electromechanical device that converts electrical energy into mechanical motion. When an electrical current flows through the solenoid's coil, it generates a magnetic field that moves a plunger or armature, which can open or close valves. This action allows for the precise control of fluid flow, enabling automation and regulation of pressure and movement in these systems. Essentially, solenoids serve as switches or actuators that facilitate the operation of various components in pneumatic and hydraulic applications.