What is the difference between active and semi-active suspension in the Audi A8?

I've noticed that some models of the Audi A8 have active suspension while others have semi-active suspension. What's the difference and which one should I go for?

Active suspension uses electronic sensors and hydraulic systems to constantly adjust the damping of each wheel, providing a smoother and more controlled ride. Semi-active suspension uses passive dampers that can be electronically adjusted on-demand, so it is not as dynamic as active suspension.