A hydraulic jack is a tool used to lift heavy objects, such as cars or machinery, with ease. It operates on the principle of hydraulics, which uses liquid pressure to create force. When you pump the handle, hydraulic fluid moves through the system, allowing the jack to lift the load. This makes it much easier to change a tire or perform maintenance on vehicles. These jacks come in various types, including floor jacks and bottle jacks, each designed for specific lifting tasks. They are essential for mechanics and DIY enthusiasts alike, providing safety and efficiency when working with heavy items.