Shock absorbers or suspension dampers, are devices that absorb shock. This regulates the movement of springs and suspensions, preventing infamous body roll during high-speed turns. They are generally made of a hollow metal tube filled with oil, gas, and a piston component.
Usually fixed behind the wheels, shocks work in conjunction with coil or leaf springs to absorb excess energy. This helps minimize impact when going over bumps or potholes. A vehicle without shocks would be like a helmet with no padding on the inside. Every time you hit a bump, there would be nothing to dissipate the energy. Shocks absorb excess energy by minimizing the springs' movement, preventing a ride that feels like a turbulent bouncy house.