Suspension Designs
      
      
Initially, car suspensions were borrowed from the 
horse and buggy, which used flexible metal bars or 
leaf springs to buffer the jarring between the 
wheels/axles and the carriage.  When the car 
crosses a bump, the spring bends by the rise of 
the bump and the body stays fairly flat.  However 
before the spring bent back to its original shape it 
shook a few more times.  Boing, boing, boing, 
boing...and so on.  So leaf springs replaced a sharp 
jarring bump with a soft bounce and motion 
sickness.
A thicker leaf spring would stop bouncing sooner, 
but it wouldn't absorb all of the bump, it was 
stiffer.  A thinner spring would absorb more of the 
bump, but it would continue to bounce after the 
bump...boing boing boing-well you get the point.  
So you could chose how soft or firm your 
suspension would be, based on how thick the leaf 
spring was.  But, there was always a trade-off, you 
could have both soft ride and but not keep your 
lunch down...until the shock absorber.
The shock absorber is designed to minimize or 
'absorb' the bouncing following a bump.  Modern 
shock absorbers use a sealed tube filled with oil in 
which a rod with a piston is immersed.  The tube is 
attached to the body, and the rod is attached to 
the wheels (or the reverse-you pick).  When the 
car goes over a bump the piston moves with the 
suspension, but in the oil.  The oil slows the 
movement of the piston, the same way water 
slows someone trying to run through it. It slows 
the movement so much that the bouncing is barely 
noticeable.  With a shock absorber, you can have a 
soft spring and not have lots of bouncing...no 
more trade-off, no more nausea.
As cars became faster and heavier, engineers 
looked to improve the ride comfort and handling.  
The leaf spring design was improved somewhat 
although eventually other types of suspensions 
were developed.
      
      
Basic suspension solid mount vs. leaf springs
      
                  
            
            Gas Charged Shock 
Absorber Diagram
      
            Gas Shock absorbers compressed