A hydraulic press is a machine that uses liquid pressure to compress or shape materials. It operates on the principle of Pascal's law, which states that pressure applied to a confined fluid is transmitted equally in all directions. This allows the press to exert a large amount of force on objects, making it useful for tasks like metal forming, crushing, and molding. In a hydraulic press, a small piston pushes hydraulic fluid into a larger piston, amplifying the force applied. This technology is commonly used in industries such as automotive, manufacturing, and recycling, where heavy materials need to be shaped or compacted efficiently.