What is the primary function of hydraulic systems?

The primary function of hydraulic systems is to transmit power through the use of liquids. Hydraulic systems make use of incompressible fluids, typically oil or water, to transmit force from one location to another. By utilizing Pascal's principle, which states that pressure applied to a confined fluid is transmitted undiminished in all directions, hydraulic systems can efficiently amplify force. This allows for the operation of heavy machinery and tools, enabling tasks like lifting, pressing, and moving objects that would be difficult or impossible to manage using mechanical systems alone.

The other options do not capture the essence of what hydraulic systems are designed to accomplish. Converting mechanical energy into thermal energy does not relate to the power transmission aspect, while creating pneumatic pressure pertains to pneumatic systems that utilize compressed gases, not liquids. Enhancing system visibility and safety is also outside the primary function of hydraulic systems, as visibility and safety are operational considerations rather than primary functionalities.