Hydraulics is the branch of science and engineering that deals with the mechanical properties of liquids and how they can be used to transmit power, generate force, or perform work. Liquids (especially water or oil) are nearly incompressible, so when pressure is applied in one part of a closed system, it’s transmitted equally throughout the liquid — this is Pascal’s Law. That principle allows us to multiply force, control motion, and operate machinery.

Main areas in hydraulics:

• Hydrostatics – liquids at rest (e.g., fluid pressure in tanks or dams).
• Hydrodynamics – liquids in motion (e.g., flow in pipes, pumps, turbines).
• Applied hydraulics – using pressurized fluids in systems like:
• Hydraulic lifts
  • Excavator arms
  • Aircraft control systems
  • Brake systems in vehicles

Key components in hydraulic systems:

• Pump – moves the liquid and creates flow.
• Actuator (e.g., cylinder or motor) – converts fluid pressure into mechanical motion.
• Valves – control flow and direction.
• Reservoir – stores fluid.