The work of shock absorbers is primarily to reduce the oscillations, up and down motions or vibrations your car makes during movement on uneven roads. It also enables your car to remain stable particularly at high speeds. 

A car with a bad shock absorber will result in a very uncomfortable  driving experience. The uncontrolled oscillations produced can result in damage to the under parts of your car. Occupants in your car too will have a rough ride.

Shock absorbers also known as dampers convert kinetic energy to heat which is in turn dissipated into the surroundings.

There are two types of shock absorbers;The pneumatic and the hydraulic types. 

The first type uses highly compressed gas as the damping component while the second type uses a viscous fluid as the main damping component

The hydraulic type is the most commonly used in vehicles.

Your car normally will have four shock absorbers, one by the inner side of each tire.

A major sign of a faulty or damaged shock absorber is hydraulic fluid leakage. You will see it on the body of the shock absorber.

To avoid damage to your shock absorbers, make sure to drive carefully on uneven roads. Avoid strong impacts into portholes or bumps.