Hydraulic systems use liquids to transmit power and control movement. They operate based on Pascal's principle, which states that pressure applied to a confined fluid is transmitted equally in all directions. Common components include pumps, cylinders, and valves, which work together to create force and motion. These systems are widely used in various applications, such as construction equipment, automobiles, and industrial machinery. For example, excavators utilize hydraulic systems to lift heavy loads and perform precise movements, making them essential for construction tasks. Their efficiency and power make hydraulic systems a vital technology in many industries.