Hydraulic suspension is a system used in vehicles to improve ride quality and handling. It utilizes fluid-filled cylinders, or shocks, that adjust the vehicle's height and stiffness based on road conditions. This allows for a smoother ride by absorbing bumps and vibrations. The system works by using hydraulic fluid to transfer force between components. When the vehicle encounters a bump, the fluid moves within the cylinders, allowing the suspension to compress and extend as needed. This technology is commonly found in luxury cars and some off-road vehicles, enhancing comfort and stability during driving.