Hydraulic power transmission is one of the oldest forms of power transmission. Modern hydraulics are used for driving a wide range of machines. With the hydraulic technology control of speed, high forces and torques of linear and rotary movements in combination with highly accurate position and velocity control is possible. For manufacturers, users and service technicians of machines with hydraulic technology it is important to gain insight into the fascinating world of hydraulics. This Technical instruction is a translation and update of the 6-th edition of the Dutch version of Hydraulics. The first edition was published in 1989. The purpose of this technical training course is: - to gain insight in the application and operation of hydraulic systems; - to learn how to read a hydraulic diagram (functional thinking), the graphical symbols are according to ISO 1219-1. - to gain insight into the function and operation of the components; - to gain insight in the relation between the components in a hydraulic system, the so called 'system technology'. Included are topics such as pump control (pressure and load sensing control), proportional and servo hydraulics. More than 75% of failures in hydraulic systems are directly or indirectly the result of improper or inadequate conditioning. So conditioning of the system and contamination control are very important in relation to the downtime and lifetime of an installation. This issue is discussed in the chapter 'conditioning'. Further information is available on our website: - a presentation of each chapter with all the graphics; - extra presentations; - additional animations and videos in the presentations. Go to www.mkpublishing.nl/hydraulics. The login details can be found in the book. 1. Hydraulics 2. Hydraulic diagrams 3. Hydraulic pumps 4. Hydraulic actuators 5. Direction control valves 6. Pressure control valves 7. Flow control 8. Check valves and counter balance valves 9. Conditioning 10. Accumulator 11. Pump controls 12. Hydrostatic transmission 13. Proportional and servo hydraulics 14. Manifolds 15. Pipes, hoses and connections 16. Hydraulic fluids 17. Maintenance