5.1 Introduction 5.2 Directional Control Valves 5.3 Pressure Operated Valves 5.4 Flow Control Valves 5.5 Manifold Valves and Cartridge Valves 5.6 Electro-Hydraulic Servo Valves 5.7 Electro-Hydraulic Proportional Valves 5.8 Electro-Hydraulic Digital Valves