Can someone please explain the difference please, and what I should use on my car ? It might sound like a newbie question but I have asked about and it sounds like a lot of people are telling me different things.

 

strut = spring over the piston.
shock = independent piston and spring.

Am I right? Thats what I think.

 

A shock only controls suspension movement. A strut does that and is a structural suspension part. If you take a shock out, the suspension/hub is still fully connected. If you take a strut out, the wheel/hub flops around.

Put another way, the strut takes side loading and vertical loading. A shock only takes vertical loading.

What you use depends on the suspension design. Hondas with upper/lower control arms use shocks. Old hondas, pre '88, and new civics use struts. The strut body and shaft have to be built stronger to take the side loads. The basic geometry of the control arm suspension is superior for handling, generally speaking. A '90 crx has the control arm setup and uses shocks.